ConfirmSpreadingModal の改善点:

groupedEntries（肥料別リスト表示）→ layout（圃場×肥料のマトリクス表）に変更 ✅ 施肥計画編集画面と同じ「圃場名 / 面積(反) / 肥料列... / 合計」のテーブル構造に統一 ✅ 各セルに計画値ラベル + 実績入力欄を縦並び ✅ 列合計（肥料別）・行合計（圃場別）・総合計を追加 ✅ 計画情報サマリーカード（年度・品種・圃場数・肥料数）を追加 ✅ 操作ガイド（sky色バナー）を追加 ✅ モーダル幅を max-w-4xl → max-w-[95vw] に拡大（マトリクス表に合わせて） ✅ ドキュメント更新: document/13_マスタードキュメント_施肥計画編.md — 在庫引当・散布確定・確定取消 API を追記 ✅ 改善案/在庫管理機能実装案.md — 微修正 ✅
完璧に動作しています。
2026-03-15 13:48:48 +09:00 · 2026-03-15 13:28:02 +09:00 · 2026-03-14 17:29:05 +09:00 · 2026-03-14 15:42:47 +09:00 · 2026-03-14 15:03:09 +09:00 · 2026-03-13 18:29:03 +09:00
39 changed files with 188806 additions and 39 deletions
--- a/.claude/settings.json
+++ b/.claude/settings.json
@@ -56,7 +56,15 @@
      "Bash(BASE=\"http://localhost/api/w/admins\")",
      "Bash(__NEW_LINE_ac825b6748572380__ curl -s -H \"Authorization: Bearer $TOKEN\" \"$BASE/variables/list\")",
      "Bash(__NEW_LINE_becbcae8f0f5a9e3__ curl -s -H \"Authorization: Bearer $TOKEN\" \"$BASE/variables/list\" -o /tmp/vars.json)",
-      "Bash(git add:*)"
+      "Bash(git add:*)",
+      "Bash(xargs cat:*)",
+      "Bash(xargs grep:*)",
+      "Bash(TOKEN=\"eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJ0b2tlbl90eXBlIjoiYWNjZXNzIiwiZXhwIjoxNzczNTY4MTAxLCJpYXQiOjE3NzM0ODE3MDEsImp0aSI6ImM1N2EyNzVjMzkyNTRmMjFiZmUxMzA4ZmU4ZjQ3ZWExIiwidXNlcl9pZCI6Mn0.LOZIpPOHN48YZuf7UBaDrPJfxb12hIm15QRnUPc9sYM\" __NEW_LINE_dd08c8854e486d12__ echo \"=== Fertilization Plans \\(check is_confirmed/confirmed_at\\) ===\" curl -s http://localhost:8000/api/fertilizer/plans/?year=2026 -H \"Authorization: Bearer $TOKEN\")",
+      "Bash(python -m json.tool)",
+      "Bash(TOKEN=\"eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJ0b2tlbl90eXBlIjoiYWNjZXNzIiwiZXhwIjoxNzczNTY4MTAxLCJpYXQiOjE3NzM0ODE3MDEsImp0aSI6ImM1N2EyNzVjMzkyNTRmMjFiZmUxMzA4ZmU4ZjQ3ZWExIiwidXNlcl9pZCI6Mn0.LOZIpPOHN48YZuf7UBaDrPJfxb12hIm15QRnUPc9sYM\" __NEW_LINE_0b7fd53b80bd968a__ echo \"=== Stock summary \\(should show reserved\\) ===\" curl -s http://localhost:8000/api/materials/stock-summary/?material_type=fertilizer -H \"Authorization: Bearer $TOKEN\")",
+      "Read(//c/Users/akira/Develop/keinasystem_t02/**)",
+      "Bash(TOKEN=\"eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJ0b2tlbl90eXBlIjoiYWNjZXNzIiwiZXhwIjoxNzczNTY4MTAxLCJpYXQiOjE3NzM0ODE3MDEsImp0aSI6ImM1N2EyNzVjMzkyNTRmMjFiZmUxMzA4ZmU4ZjQ3ZWExIiwidXNlcl9pZCI6Mn0.LOZIpPOHN48YZuf7UBaDrPJfxb12hIm15QRnUPc9sYM\" __NEW_LINE_74a785697e4cd919__ echo \"=== After confirm: stock summary ===\" curl -s http://localhost:8000/api/materials/stock-summary/?material_type=fertilizer -H \"Authorization: Bearer $TOKEN\")",
+      "Bash(git diff:*)"
    ],
    "additionalDirectories": [
      "C:\\Users\\akira\\AppData\\Local\\Temp"
--- a/.gitignore
+++ b/.gitignore
@@ -13,3 +13,5 @@ out/
 db.sqlite3
 postgres_data/
 nul
+
+*.tsbuildinfo
--- a/CODEX.md
+++ b/CODEX.md
@@ -0,0 +1,830 @@
+# CODEX 実装指示書: 施肥計画連携・引当機能（Phase 1.5）
+
+> 作成日: 2026-03-14
+> 対象: `keinasystem_t02`
+> 設計案: `改善案/在庫管理機能実装案.md`（セクション23が対象）
+> 前提: Phase 1（セクション1〜16）は実装済み。`apps/materials` が稼働中。
+
+---
+
+## 0. 実装の前提と絶対ルール
+
+### 現在のプロジェクト構造（Phase 1 実装済み）
+
+```
+keinasystem_t02/
+├── backend/
+│   ├── keinasystem/
+│   │   ├── settings.py        # apps.materials 登録済み
+│   │   └── urls.py            # /api/materials/ 登録済み
+│   └── apps/
+│       ├── fields/            # 圃場管理（Field モデル）
+│       ├── plans/             # 作付け計画（Crop, Variety モデル）
+│       ├── fertilizer/        # 施肥計画（Fertilizer, FertilizationPlan, FertilizationEntry 等）
+│       │   └── models.py      # Fertilizer.material = OneToOneField(Material) 追加済み
+│       └── materials/         # 在庫管理（Material, FertilizerProfile, PesticideProfile, StockTransaction）
+│           └── models.py      # Phase 1 で作成済み
+└── frontend/
+    └── src/
+        ├── types/index.ts         # Material, StockTransaction, StockSummary 定義済み
+        ├── lib/api.ts             # axios インスタンス（変更不要）
+        ├── components/
+        │   └── Navbar.tsx         # 在庫管理メニュー追加済み
+        └── app/
+            ├── fertilizer/        # 施肥計画（既存）← 今回変更対象
+            │   ├── page.tsx
+            │   ├── [id]/edit/page.tsx
+            │   └── _components/FertilizerEditPage.tsx
+            └── materials/         # 在庫管理（Phase 1 で作成済み）← 今回変更対象
+                ├── page.tsx
+                └── _components/StockOverview.tsx
+```
+
+### 技術スタック
+
+- Backend: Django 5.2 + Django REST Framework + PostgreSQL 16
+- Frontend: Next.js 14 (App Router) + TypeScript strict + Tailwind CSS
+- 認証: SimpleJWT（ヘッダー `Authorization: Bearer <token>`）
+- Docker: `docker compose exec backend python manage.py ...`
+
+### 絶対ルール
+
+1. **既存の施肥計画 CRUD（作成・編集・削除・PDF）を壊さない**
+2. **`FertilizationEntry → Fertilizer` の FK は変更しない**
+3. **`Fertilizer` モデルは改名・削除しない**
+4. **フロントエンドでは `alert()` / `confirm()` を使わない**（インラインバナーで表示）
+5. **TypeScript strict mode に従う**
+6. **Next.js 14 では `params` は通常のオブジェクト**（`use(params)` は使わない）
+7. **マイグレーションは段階的に。1つのマイグレーションで複数の大きな変更をしない**
+
+---
+
+## 1. 実装スコープ（Phase 1.5）
+
+### やること
+
+1. `StockTransaction` に `reserve` タイプ追加
+2. `StockTransaction` に `fertilization_plan` FK 追加（マイグレーション）
+3. `FertilizationPlan` に `is_confirmed` / `confirmed_at` 追加（マイグレーション）
+4. 在庫集計 API に `reserved_stock` / `available_stock` 追加
+5. 施肥計画の保存時に引当（reserve）を自動作成
+6. 施肥計画の削除時に引当を自動解除
+7. 散布確定 API（`confirm_spreading`）
+8. 肥料在庫一覧 API（施肥計画画面用）
+9. フロントエンド: 在庫一覧に引当表示追加
+10. フロントエンド: 施肥計画編集に在庫参照追加
+11. フロントエンド: 散布確定画面
+12. フロントエンド: 施肥計画一覧に確定状態表示追加
+
+### やらないこと
+
+- 公式データ同期（FAMIC、農水省）
+- 別名辞書（MaterialAlias）
+- LLM 調査支援
+- 農薬散布計画の在庫連携
+
+---
+
+## 2. バックエンド: モデル変更
+
+### 2.1 StockTransaction の変更 (`backend/apps/materials/models.py`)
+
+**現在のコード**（変更が必要な箇所のみ抜粋）:
+
+```python
+class StockTransaction(models.Model):
+    class TransactionType(models.TextChoices):
+        PURCHASE = 'purchase', '入庫'
+        USE = 'use', '使用'
+        ADJUSTMENT_PLUS = 'adjustment_plus', '棚卸増'
+        ADJUSTMENT_MINUS = 'adjustment_minus', '棚卸減'
+        DISCARD = 'discard', '廃棄'
+
+    INCREASE_TYPES = {
+        TransactionType.PURCHASE,
+        TransactionType.ADJUSTMENT_PLUS,
+    }
+    DECREASE_TYPES = {
+        TransactionType.USE,
+        TransactionType.ADJUSTMENT_MINUS,
+        TransactionType.DISCARD,
+    }
+```
+
+**変更後**:
+
+```python
+class StockTransaction(models.Model):
+    class TransactionType(models.TextChoices):
+        PURCHASE = 'purchase', '入庫'
+        USE = 'use', '使用'
+        RESERVE = 'reserve', '引当'          # ← 追加
+        ADJUSTMENT_PLUS = 'adjustment_plus', '棚卸増'
+        ADJUSTMENT_MINUS = 'adjustment_minus', '棚卸減'
+        DISCARD = 'discard', '廃棄'
+
+    INCREASE_TYPES = {
+        TransactionType.PURCHASE,
+        TransactionType.ADJUSTMENT_PLUS,
+    }
+    DECREASE_TYPES = {
+        TransactionType.USE,
+        TransactionType.RESERVE,             # ← 追加
+        TransactionType.ADJUSTMENT_MINUS,
+        TransactionType.DISCARD,
+    }
+```
+
+**フィールド追加**（既存フィールドの後に追加）:
+
+```python
+    fertilization_plan = models.ForeignKey(
+        'fertilizer.FertilizationPlan',
+        on_delete=models.SET_NULL,
+        null=True,
+        blank=True,
+        related_name='stock_reservations',
+        verbose_name='施肥計画',
+    )
+```
+
+### 2.2 FertilizationPlan の変更 (`backend/apps/fertilizer/models.py`)
+
+**フィールド追加**（既存フィールドの後に追加）:
+
+```python
+    is_confirmed = models.BooleanField(
+        default=False, verbose_name='散布確定済み'
+    )
+    confirmed_at = models.DateTimeField(
+        null=True, blank=True, verbose_name='散布確定日時'
+    )
+```
+
+### 2.3 マイグレーション
+
+#### マイグレーション1: `backend/apps/materials/migrations/0002_stocktransaction_fertilization_plan.py`
+
+```python
+import django.db.models.deletion
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('materials', '0001_initial'),
+        ('fertilizer', '0005_fertilizer_material'),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name='stocktransaction',
+            name='fertilization_plan',
+            field=models.ForeignKey(
+                blank=True,
+                null=True,
+                on_delete=django.db.models.deletion.SET_NULL,
+                related_name='stock_reservations',
+                to='fertilizer.fertilizationplan',
+                verbose_name='施肥計画',
+            ),
+        ),
+    ]
+```
+
+注意: `TransactionType` の choices 変更はマイグレーション不要（Django は choices をDBレベルで強制しないため）。
+
+#### マイグレーション2: `backend/apps/fertilizer/migrations/0006_fertilizationplan_confirmation.py`
+
+```python
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('fertilizer', '0005_fertilizer_material'),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name='fertilizationplan',
+            name='is_confirmed',
+            field=models.BooleanField(default=False, verbose_name='散布確定済み'),
+        ),
+        migrations.AddField(
+            model_name='fertilizationplan',
+            name='confirmed_at',
+            field=models.DateTimeField(
+                blank=True, null=True, verbose_name='散布確定日時'
+            ),
+        ),
+    ]
+```
+
+---
+
+## 3. バックエンド: 引当ロジック
+
+### 3.1 引当の作成・解除ヘルパー関数
+
+`backend/apps/materials/stock_service.py` を新規作成:
+
+```python
+from django.db import transaction
+from .models import StockTransaction
+
+
+@transaction.atomic
+def create_reserves_for_plan(plan):
+    """施肥計画の全エントリについて引当トランザクションを作成する。
+    既存の引当は全削除してから再作成する（差分更新ではなく全置換）。
+    """
+    # 既存の引当を全削除
+    StockTransaction.objects.filter(
+        fertilization_plan=plan,
+        transaction_type='reserve',
+    ).delete()
+
+    # plan が確定済みなら引当を作らない（use が既にある）
+    if plan.is_confirmed:
+        return
+
+    for entry in plan.entries.select_related('fertilizer__material'):
+        material = getattr(entry.fertilizer, 'material', None)
+        if material is None:
+            # Fertilizer.material が未連携の場合はスキップ
+            continue
+        StockTransaction.objects.create(
+            material=material,
+            transaction_type='reserve',
+            quantity=entry.bags,
+            occurred_on=plan.updated_at.date() if plan.updated_at else plan.created_at.date(),
+            note=f'施肥計画「{plan.name}」からの引当',
+            fertilization_plan=plan,
+        )
+
+
+@transaction.atomic
+def delete_reserves_for_plan(plan):
+    """施肥計画に紐づく全引当トランザクションを削除する。"""
+    StockTransaction.objects.filter(
+        fertilization_plan=plan,
+        transaction_type='reserve',
+    ).delete()
+
+
+@transaction.atomic
+def confirm_spreading(plan, actual_entries):
+    """散布確定: 引当を削除し、実績数量で use トランザクションを作成する。
+
+    actual_entries: list of dict
+        [{"field_id": int, "fertilizer_id": int, "actual_bags": Decimal}, ...]
+        actual_bags=0 の行は引当解除のみ（use を作成しない）
+    """
+    from apps.fertilizer.models import Fertilizer
+    from django.utils import timezone
+
+    # 既存の引当を全削除
+    delete_reserves_for_plan(plan)
+
+    # 実績 > 0 の行について use トランザクションを作成
+    today = timezone.now().date()
+    for entry_data in actual_entries:
+        actual_bags = entry_data['actual_bags']
+        if actual_bags <= 0:
+            continue
+
+        try:
+            fertilizer = Fertilizer.objects.select_related('material').get(
+                id=entry_data['fertilizer_id']
+            )
+        except Fertilizer.DoesNotExist:
+            continue
+
+        material = getattr(fertilizer, 'material', None)
+        if material is None:
+            continue
+
+        StockTransaction.objects.create(
+            material=material,
+            transaction_type='use',
+            quantity=actual_bags,
+            occurred_on=today,
+            note=f'施肥計画「{plan.name}」散布確定',
+            fertilization_plan=plan,
+        )
+
+    # 計画を確定済みに更新
+    plan.is_confirmed = True
+    plan.confirmed_at = timezone.now()
+    plan.save(update_fields=['is_confirmed', 'confirmed_at'])
+```
+
+### 3.2 施肥計画 ViewSet の変更 (`backend/apps/fertilizer/views.py`)
+
+既存の `FertilizationPlanViewSet` に以下の変更を加える。
+
+#### 保存時の引当自動作成
+
+`perform_create` と `perform_update` をオーバーライドして、保存後に引当を作成する:
+
+```python
+from apps.materials.stock_service import (
+    create_reserves_for_plan,
+    delete_reserves_for_plan,
+    confirm_spreading as confirm_spreading_service,
+)
+
+class FertilizationPlanViewSet(viewsets.ModelViewSet):
+    # ... 既存コード ...
+
+    def perform_create(self, serializer):
+        instance = serializer.save()
+        create_reserves_for_plan(instance)
+
+    def perform_update(self, serializer):
+        instance = serializer.save()
+        create_reserves_for_plan(instance)
+
+    def perform_destroy(self, instance):
+        delete_reserves_for_plan(instance)
+        instance.delete()
+```
+
+#### 散布確定アクション
+
+```python
+from rest_framework.decorators import action
+from decimal import Decimal
+
+class FertilizationPlanViewSet(viewsets.ModelViewSet):
+    # ... 既存コード ...
+
+    @action(detail=True, methods=['post'], url_path='confirm_spreading')
+    def confirm_spreading(self, request, pk=None):
+        plan = self.get_object()
+
+        if plan.is_confirmed:
+            return Response(
+                {'detail': 'この計画は既に散布確定済みです。'},
+                status=status.HTTP_400_BAD_REQUEST,
+            )
+
+        entries_data = request.data.get('entries', [])
+        if not entries_data:
+            return Response(
+                {'detail': '実績データが空です。'},
+                status=status.HTTP_400_BAD_REQUEST,
+            )
+
+        actual_entries = []
+        for entry in entries_data:
+            actual_entries.append({
+                'field_id': entry['field_id'],
+                'fertilizer_id': entry['fertilizer_id'],
+                'actual_bags': Decimal(str(entry.get('actual_bags', 0))),
+            })
+
+        confirm_spreading_service(plan, actual_entries)
+
+        serializer = self.get_serializer(plan)
+        return Response(serializer.data)
+```
+
+### 3.3 施肥計画 Serializer の変更 (`backend/apps/fertilizer/serializers.py`)
+
+`FertilizationPlanSerializer`（読み取り用）に `is_confirmed` / `confirmed_at` を追加:
+
+```python
+class FertilizationPlanSerializer(serializers.ModelSerializer):
+    # ... 既存フィールド ...
+    is_confirmed = serializers.BooleanField(read_only=True)
+    confirmed_at = serializers.DateTimeField(read_only=True)
+
+    class Meta:
+        model = FertilizationPlan
+        fields = [
+            # ... 既存フィールド ...,
+            'is_confirmed', 'confirmed_at',
+        ]
+```
+
+---
+
+## 4. バックエンド: 在庫集計 API の変更
+
+### 4.1 StockSummarySerializer の変更 (`backend/apps/materials/serializers.py`)
+
+```python
+class StockSummarySerializer(serializers.Serializer):
+    material_id = serializers.IntegerField()
+    name = serializers.CharField()
+    material_type = serializers.CharField()
+    material_type_display = serializers.CharField()
+    maker = serializers.CharField()
+    stock_unit = serializers.CharField()
+    stock_unit_display = serializers.CharField()
+    is_active = serializers.BooleanField()
+    current_stock = serializers.DecimalField(max_digits=10, decimal_places=3)
+    reserved_stock = serializers.DecimalField(max_digits=10, decimal_places=3)   # ← 追加
+    available_stock = serializers.DecimalField(max_digits=10, decimal_places=3)  # ← 追加
+    last_transaction_date = serializers.DateField(allow_null=True)
+```
+
+### 4.2 StockSummaryView の変更 (`backend/apps/materials/views.py`)
+
+在庫集計のループ内で `reserved_stock` と `available_stock` を計算する:
+
+```python
+for material in queryset:
+    transactions = list(material.stock_transactions.all())
+    increase = sum(
+        txn.quantity for txn in transactions
+        if txn.transaction_type in StockTransaction.INCREASE_TYPES
+    )
+    decrease = sum(
+        txn.quantity for txn in transactions
+        if txn.transaction_type in StockTransaction.DECREASE_TYPES
+    )
+    reserved = sum(
+        txn.quantity for txn in transactions
+        if txn.transaction_type == 'reserve'
+    )
+    last_date = max((txn.occurred_on for txn in transactions), default=None)
+
+    current = increase - decrease   # 引当込みの在庫（引当分は既に引かれている）
+    results.append({
+        'material_id': material.id,
+        'name': material.name,
+        'material_type': material.material_type,
+        'material_type_display': material.get_material_type_display(),
+        'maker': material.maker,
+        'stock_unit': material.stock_unit,
+        'stock_unit_display': material.get_stock_unit_display(),
+        'is_active': material.is_active,
+        'current_stock': current + reserved,  # 引当を戻した「物理的な在庫」
+        'reserved_stock': reserved,           # 引当中の数量
+        'available_stock': current,           # 利用可能在庫（引当済み分を除く）
+        'last_transaction_date': last_date,
+    })
+```
+
+**在庫計算の定義**:
+- `current_stock`: 物理的に倉庫にある数量（入庫 - 使用 - 廃棄 ± 調整）
+- `reserved_stock`: そのうち施肥計画で引き当てられている数量
+- `available_stock`: 新しい計画に使える数量（= current_stock - reserved_stock）
+
+### 4.3 肥料在庫 API（施肥計画画面用）
+
+`backend/apps/materials/views.py` に追加:
+
+```python
+class FertilizerStockView(generics.ListAPIView):
+    """施肥計画画面用: 肥料の在庫情報を返す"""
+    permission_classes = [IsAuthenticated]
+    serializer_class = StockSummarySerializer
+
+    def get_queryset(self):
+        return None
+
+    def list(self, request, *args, **kwargs):
+        queryset = Material.objects.filter(
+            material_type='fertilizer',
+            is_active=True,
+        ).prefetch_related('stock_transactions')
+
+        results = []
+        for material in queryset:
+            transactions = list(material.stock_transactions.all())
+            increase = sum(
+                txn.quantity for txn in transactions
+                if txn.transaction_type in StockTransaction.INCREASE_TYPES
+            )
+            decrease = sum(
+                txn.quantity for txn in transactions
+                if txn.transaction_type in StockTransaction.DECREASE_TYPES
+            )
+            reserved = sum(
+                txn.quantity for txn in transactions
+                if txn.transaction_type == 'reserve'
+            )
+            current = increase - decrease
+            results.append({
+                'material_id': material.id,
+                'name': material.name,
+                'material_type': material.material_type,
+                'material_type_display': material.get_material_type_display(),
+                'maker': material.maker,
+                'stock_unit': material.stock_unit,
+                'stock_unit_display': material.get_stock_unit_display(),
+                'is_active': material.is_active,
+                'current_stock': current + reserved,
+                'reserved_stock': reserved,
+                'available_stock': current,
+                'last_transaction_date': max(
+                    (t.occurred_on for t in transactions), default=None
+                ),
+            })
+
+        serializer = StockSummarySerializer(results, many=True)
+        return Response(serializer.data)
+```
+
+`backend/apps/materials/urls.py` に追加:
+
+```python
+urlpatterns = [
+    path('', include(router.urls)),
+    path('stock-summary/', views.StockSummaryView.as_view(), name='stock-summary'),
+    path('fertilizer-stock/', views.FertilizerStockView.as_view(), name='fertilizer-stock'),  # ← 追加
+]
+```
+
+---
+
+## 5. フロントエンド: 型定義の変更
+
+### 5.1 StockTransaction 型に `reserve` 追加 (`frontend/src/types/index.ts`)
+
+**変更前**:
+```typescript
+transaction_type: 'purchase' | 'use' | 'adjustment_plus' | 'adjustment_minus' | 'discard';
+```
+
+**変更後**:
+```typescript
+transaction_type: 'purchase' | 'use' | 'reserve' | 'adjustment_plus' | 'adjustment_minus' | 'discard';
+```
+
+### 5.2 StockSummary 型に引当フィールド追加
+
+**変更前**:
+```typescript
+export interface StockSummary {
+  material_id: number;
+  name: string;
+  material_type: 'fertilizer' | 'pesticide' | 'seedling' | 'other';
+  material_type_display: string;
+  maker: string;
+  stock_unit: string;
+  stock_unit_display: string;
+  is_active: boolean;
+  current_stock: string;
+  last_transaction_date: string | null;
+}
+```
+
+**変更後**:
+```typescript
+export interface StockSummary {
+  material_id: number;
+  name: string;
+  material_type: 'fertilizer' | 'pesticide' | 'seedling' | 'other';
+  material_type_display: string;
+  maker: string;
+  stock_unit: string;
+  stock_unit_display: string;
+  is_active: boolean;
+  current_stock: string;
+  reserved_stock: string;      // ← 追加
+  available_stock: string;     // ← 追加
+  last_transaction_date: string | null;
+}
+```
+
+### 5.3 FertilizationPlan 型に確定フィールド追加
+
+既存の `FertilizationPlan` インターフェースに追加:
+
+```typescript
+export interface FertilizationPlan {
+  // ... 既存フィールド ...
+  is_confirmed: boolean;           // ← 追加
+  confirmed_at: string | null;     // ← 追加
+}
+```
+
+---
+
+## 6. フロントエンド: 画面変更
+
+### 6.1 在庫一覧の引当表示 (`frontend/src/app/materials/_components/StockOverview.tsx`)
+
+現在庫の表示を変更:
+
+**変更前**:
+```
+現在庫: 18
+```
+
+**変更後**:
+```
+在庫 18袋（引当 12袋）/ 利用可能 6袋
+```
+
+引当が0の場合は引当表示を省略する。
+
+### 6.2 施肥計画編集画面の在庫参照 (`frontend/src/app/fertilizer/_components/FertilizerEditPage.tsx`)
+
+施肥計画の編集画面（マトリクス表）で、肥料列ヘッダーに在庫情報を表示する。
+
+**追加表示**（肥料名の下に小さく）:
+```
+仁井田米有機
+在庫 18袋 / 計画計 24袋
+```
+
+計画合計が在庫を超える場合は赤文字で「不足 6袋」を表示する。
+
+**データ取得**: ページ読み込み時に `GET /api/materials/fertilizer-stock/` を呼び、
+`Fertilizer.material` の OneToOne 経由で material_id と紐づける。
+
+紐づけロジック:
+1. `GET /api/fertilizer/fertilizers/` で肥料一覧を取得（既存）
+2. `GET /api/materials/materials/?material_type=fertilizer` で Material 一覧を取得
+3. `Fertilizer.name` と `Material.name` を突き合わせる（同名で作成されているため一致する）
+
+または、Fertilizer の serializer に `material_id` を追加して直接紐づける（推奨）。
+
+**Fertilizer serializer への追加**（`backend/apps/fertilizer/serializers.py`）:
+
+```python
+class FertilizerSerializer(serializers.ModelSerializer):
+    material_id = serializers.IntegerField(source='material.id', read_only=True, default=None)
+
+    class Meta:
+        model = Fertilizer
+        fields = [
+            # ... 既存フィールド ...,
+            'material_id',
+        ]
+```
+
+### 6.3 施肥計画一覧の確定状態表示 (`frontend/src/app/fertilizer/page.tsx`)
+
+各計画行に確定状態を表示:
+
+- 未確定: 通常表示 + 「散布確定」ボタン
+- 確定済み: 背景色変更（例: 薄い青）+ 「確定済み ✓」バッジ + 確定日時
+
+### 6.4 散布確定画面
+
+**実装方法**: モーダルまたは専用ページ。施肥計画一覧の「散布確定」ボタンから起動。
+
+**画面構成**:
+
+```
+┌─ 散布確定: 「計画名」──────────────────────────────┐
+│                                                     │
+│  肥料: 仁井田米有機                                  │
+│  ┌─────────────┬──────┬──────────┐                  │
+│  │ 圃場         │ 計画  │ 実績      │                  │
+│  ├─────────────┼──────┼──────────┤                  │
+│  │ 上の田       │ 3袋   │ [  3   ]  │                  │
+│  │ 下の田       │ 4袋   │ [  3.5 ]  │                  │
+│  │ 山の畑       │ 2袋   │ [  0   ]  │                  │
+│  └─────────────┴──────┴──────────┘                  │
+│                                                     │
+│  肥料: 土佐勤農党                                    │
+│  ┌─────────────┬──────┬──────────┐                  │
+│  │ 圃場         │ 計画  │ 実績      │                  │
+│  ├─────────────┼──────┼──────────┤                  │
+│  │ ...          │ ...   │ [  ... ]  │                  │
+│  └─────────────┴──────┴──────────┘                  │
+│                                                     │
+│                      [キャンセル] [一括確定]          │
+└─────────────────────────────────────────────────────┘
+```
+
+**動作**:
+1. 施肥計画のエントリを肥料ごとにグループ化して表示
+2. 「実績」列は計画値がプリセットされた数値入力欄
+3. 修正が必要な行だけ数値を変更する
+4. 実績を0にした行は「未散布」として引当解除される
+5. 「一括確定」で `POST /api/fertilizer/plans/{id}/confirm_spreading/` を呼ぶ
+
+**API リクエスト**:
+```json
+{
+  "entries": [
+    {"field_id": 1, "fertilizer_id": 3, "actual_bags": 3.0},
+    {"field_id": 2, "fertilizer_id": 3, "actual_bags": 3.5},
+    {"field_id": 3, "fertilizer_id": 3, "actual_bags": 0}
+  ]
+}
+```
+
+---
+
+## 7. API エンドポイント一覧（Phase 1.5 で追加・変更）
+
+### 新規
+
+| メソッド | パス | 認証 | 説明 |
+|----------|------|------|------|
+| POST | `/api/fertilizer/plans/{id}/confirm_spreading/` | JWT | 散布確定（reserve→use変換） |
+| GET | `/api/materials/fertilizer-stock/` | JWT | 肥料在庫一覧（施肥計画画面用） |
+
+### 変更
+
+| メソッド | パス | 変更内容 |
+|----------|------|----------|
+| POST/PUT | `/api/fertilizer/plans/` | 保存後に reserve 自動作成 |
+| DELETE | `/api/fertilizer/plans/{id}/` | 削除前に reserve 自動削除 |
+| GET | `/api/fertilizer/plans/` | レスポンスに `is_confirmed`, `confirmed_at` 追加 |
+| GET | `/api/fertilizer/fertilizers/` | レスポンスに `material_id` 追加 |
+| GET | `/api/materials/stock-summary/` | レスポンスに `reserved_stock`, `available_stock` 追加 |
+
+---
+
+## 8. 実装順序（厳守）
+
+### Step 1: バックエンド — モデル・マイグレーション
+1. `apps/materials/models.py` に `reserve` タイプ追加、`DECREASE_TYPES` 更新、`fertilization_plan` FK 追加
+2. `apps/fertilizer/models.py` に `is_confirmed`, `confirmed_at` 追加
+3. `apps/materials/migrations/0002_stocktransaction_fertilization_plan.py` 作成
+4. `apps/fertilizer/migrations/0006_fertilizationplan_confirmation.py` 作成
+
+### Step 2: バックエンド — ロジック・API
+5. `apps/materials/stock_service.py` 作成（引当作成・解除・散布確定ヘルパー）
+6. `apps/fertilizer/views.py` の `FertilizationPlanViewSet` に `perform_create`, `perform_update`, `perform_destroy` オーバーライド追加
+7. `apps/fertilizer/views.py` に `confirm_spreading` アクション追加
+8. `apps/fertilizer/serializers.py` に `is_confirmed`, `confirmed_at` 追加
+9. `apps/fertilizer/serializers.py` の `FertilizerSerializer` に `material_id` 追加
+10. `apps/materials/serializers.py` の `StockSummarySerializer` に `reserved_stock`, `available_stock` 追加
+11. `apps/materials/views.py` の `StockSummaryView` で引当集計を追加
+12. `apps/materials/views.py` に `FertilizerStockView` 追加
+13. `apps/materials/urls.py` に `fertilizer-stock/` パス追加
+
+### Step 3: フロントエンド
+14. `types/index.ts` に `reserve` タイプ追加、`StockSummary` に引当フィールド追加、`FertilizationPlan` に確定フィールド追加
+15. `app/materials/_components/StockOverview.tsx` に引当表示追加
+16. `app/materials/page.tsx` の `StockTransactionForm` に `reserve` オプション追加（手動引当は不要なら省略可）
+17. `app/fertilizer/_components/FertilizerEditPage.tsx` に在庫参照表示追加
+18. `app/fertilizer/page.tsx` に確定状態表示・散布確定ボタン追加
+19. `app/fertilizer/_components/ConfirmSpreadingModal.tsx` 新規作成（散布確定モーダル）
+
+---
+
+## 9. テスト確認項目
+
+### バックエンド
+- [ ] マイグレーション適用成功（materials 0002, fertilizer 0006）
+- [ ] 施肥計画を保存すると、各エントリに対応する reserve トランザクションが作成される
+- [ ] 施肥計画を更新すると、古い reserve が削除され新しい reserve が作成される
+- [ ] 施肥計画を削除すると、reserve が全て削除される
+- [ ] `GET /api/materials/stock-summary/` で `reserved_stock` と `available_stock` が返る
+- [ ] 入庫10 → 引当3 → `current_stock=10`, `reserved_stock=3`, `available_stock=7`
+- [ ] `POST /api/fertilizer/plans/{id}/confirm_spreading/` で reserve が use に変換される
+- [ ] 確定済み計画に再度 confirm_spreading すると 400 エラー
+- [ ] actual_bags=0 の行は reserve 削除のみ（use は作成しない）
+- [ ] `Fertilizer.material` が null の Fertilizer は引当をスキップする
+- [ ] 既存の施肥計画 CRUD（作成・編集・削除・PDF）が壊れていない
+
+### フロントエンド
+- [ ] 在庫一覧に引当数量と利用可能在庫が表示される
+- [ ] 施肥計画編集画面に肥料ごとの在庫情報が表示される
+- [ ] 施肥計画一覧に確定状態（未確定/確定済み）が表示される
+- [ ] 散布確定モーダルが開き、計画値がプリセットされる
+- [ ] 実績を修正して一括確定できる
+- [ ] 確定後、計画が「確定済み」表示に変わる
+- [ ] 確定済みの計画には「散布確定」ボタンが表示されない
+
+---
+
+## 10. 既存コードへの変更一覧（影響範囲）
+
+| ファイル | 変更内容 |
+|----------|----------|
+| `backend/apps/materials/models.py` | `StockTransaction` に `reserve` タイプ・`fertilization_plan` FK 追加 |
+| `backend/apps/materials/serializers.py` | `StockSummarySerializer` に `reserved_stock`・`available_stock` 追加 |
+| `backend/apps/materials/views.py` | `StockSummaryView` 集計変更、`FertilizerStockView` 追加 |
+| `backend/apps/materials/urls.py` | `fertilizer-stock/` パス追加 |
+| `backend/apps/materials/stock_service.py` | **新規作成** — 引当ロジック |
+| `backend/apps/materials/migrations/0002_...py` | **新規作成** — fertilization_plan FK |
+| `backend/apps/fertilizer/models.py` | `FertilizationPlan` に `is_confirmed`・`confirmed_at` 追加 |
+| `backend/apps/fertilizer/views.py` | `perform_create/update/destroy` オーバーライド、`confirm_spreading` アクション追加 |
+| `backend/apps/fertilizer/serializers.py` | `is_confirmed`・`confirmed_at`・`material_id` 追加 |
+| `backend/apps/fertilizer/migrations/0006_...py` | **新規作成** — is_confirmed, confirmed_at |
+| `frontend/src/types/index.ts` | `reserve` タイプ追加、引当フィールド追加、確定フィールド追加 |
+| `frontend/src/app/materials/_components/StockOverview.tsx` | 引当表示追加 |
+| `frontend/src/app/fertilizer/_components/FertilizerEditPage.tsx` | 在庫参照表示追加 |
+| `frontend/src/app/fertilizer/page.tsx` | 確定状態表示・散布確定ボタン追加 |
+| `frontend/src/app/fertilizer/_components/ConfirmSpreadingModal.tsx` | **新規作成** — 散布確定モーダル |
+
+---
+
+## 11. 参照すべき既存コード（実装パターンの手本）
+
+| 目的 | 参照先 |
+|------|--------|
+| 施肥計画 ViewSet（perform_create の追加先） | `backend/apps/fertilizer/views.py` |
+| 施肥計画 Serializer（フィールド追加先） | `backend/apps/fertilizer/serializers.py` |
+| 施肥計画の @action パターン（PDF アクション） | `backend/apps/fertilizer/views.py` の `pdf` アクション |
+| 在庫集計ロジック | `backend/apps/materials/views.py` の `StockSummaryView` |
+| 施肥計画編集画面（マトリクス表） | `frontend/src/app/fertilizer/_components/FertilizerEditPage.tsx` |
+| 施肥計画一覧画面 | `frontend/src/app/fertilizer/page.tsx` |
+| モーダルパターン | `frontend/src/app/materials/_components/StockTransactionForm.tsx` |
+| 在庫一覧コンポーネント | `frontend/src/app/materials/_components/StockOverview.tsx` |
--- a/all_fertilizer.zip
+++ b/all_fertilizer.zip
--- a/all_fertilizer/1.全件.csv
+++ b/all_fertilizer/1.全件.csv
--- a/backend/apps/fertilizer/migrations/0005_fertilizer_material.py
+++ b/backend/apps/fertilizer/migrations/0005_fertilizer_material.py
@@ -0,0 +1,56 @@
+import django.db.models.deletion
+from django.db import migrations, models
+
+
+def create_materials_for_existing_fertilizers(apps, schema_editor):
+    Fertilizer = apps.get_model('fertilizer', 'Fertilizer')
+    Material = apps.get_model('materials', 'Material')
+    FertilizerProfile = apps.get_model('materials', 'FertilizerProfile')
+
+    for fertilizer in Fertilizer.objects.all():
+        material = Material.objects.create(
+            name=fertilizer.name,
+            material_type='fertilizer',
+            maker=fertilizer.maker or '',
+            stock_unit='bag',
+            is_active=True,
+            notes=fertilizer.notes or '',
+        )
+        FertilizerProfile.objects.create(
+            material=material,
+            capacity_kg=fertilizer.capacity_kg,
+            nitrogen_pct=fertilizer.nitrogen_pct,
+            phosphorus_pct=fertilizer.phosphorus_pct,
+            potassium_pct=fertilizer.potassium_pct,
+        )
+        fertilizer.material = material
+        fertilizer.save(update_fields=['material'])
+
+
+def reverse_migration(apps, schema_editor):
+    Fertilizer = apps.get_model('fertilizer', 'Fertilizer')
+    Fertilizer.objects.all().update(material=None)
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('fertilizer', '0004_fertilizationplan_calc_settings'),
+        ('materials', '0001_initial'),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name='fertilizer',
+            name='material',
+            field=models.OneToOneField(
+                blank=True,
+                null=True,
+                on_delete=django.db.models.deletion.SET_NULL,
+                related_name='legacy_fertilizer',
+                to='materials.material',
+                verbose_name='資材マスタ',
+            ),
+        ),
+        migrations.RunPython(create_materials_for_existing_fertilizers, reverse_migration),
+    ]
--- a/backend/apps/fertilizer/migrations/0006_fertilizationplan_confirmation.py
+++ b/backend/apps/fertilizer/migrations/0006_fertilizationplan_confirmation.py
@@ -0,0 +1,21 @@
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('fertilizer', '0005_fertilizer_material'),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name='fertilizationplan',
+            name='is_confirmed',
+            field=models.BooleanField(default=False, verbose_name='散布確定済み'),
+        ),
+        migrations.AddField(
+            model_name='fertilizationplan',
+            name='confirmed_at',
+            field=models.DateTimeField(blank=True, null=True, verbose_name='散布確定日時'),
+        ),
+    ]
--- a/backend/apps/fertilizer/models.py
+++ b/backend/apps/fertilizer/models.py
@@ -17,6 +17,14 @@ class Fertilizer(models.Model):
        max_digits=5, decimal_places=2, blank=True, null=True, verbose_name='カリ含有率(%)'
    )
    notes = models.TextField(blank=True, null=True, verbose_name='備考')
+    material = models.OneToOneField(
+        'materials.Material',
+        on_delete=models.SET_NULL,
+        null=True,
+        blank=True,
+        related_name='legacy_fertilizer',
+        verbose_name='資材マスタ',
+    )

    class Meta:
        verbose_name = '肥料マスタ'
@@ -35,6 +43,8 @@ class FertilizationPlan(models.Model):
        related_name='fertilization_plans', verbose_name='品種'
    )
    calc_settings = models.JSONField(default=list, blank=True, verbose_name='計算設定')
+    is_confirmed = models.BooleanField(default=False, verbose_name='散布確定済み')
+    confirmed_at = models.DateTimeField(null=True, blank=True, verbose_name='散布確定日時')
    created_at = models.DateTimeField(auto_now_add=True)
    updated_at = models.DateTimeField(auto_now=True)

--- a/backend/apps/fertilizer/serializers.py
+++ b/backend/apps/fertilizer/serializers.py
@@ -3,9 +3,25 @@ from .models import Fertilizer, FertilizationPlan, FertilizationEntry, Distribut


 class FertilizerSerializer(serializers.ModelSerializer):
+    material_id = serializers.SerializerMethodField()
+
    class Meta:
        model = Fertilizer
-        fields = '__all__'
+        fields = [
+            'id',
+            'name',
+            'maker',
+            'capacity_kg',
+            'nitrogen_pct',
+            'phosphorus_pct',
+            'potassium_pct',
+            'notes',
+            'material',
+            'material_id',
+        ]
+
+    def get_material_id(self, obj):
+        return obj.material_id


 class FertilizationEntrySerializer(serializers.ModelSerializer):
@@ -26,12 +42,15 @@ class FertilizationPlanSerializer(serializers.ModelSerializer):
    entries = FertilizationEntrySerializer(many=True, read_only=True)
    field_count = serializers.SerializerMethodField()
    fertilizer_count = serializers.SerializerMethodField()
+    is_confirmed = serializers.BooleanField(read_only=True)
+    confirmed_at = serializers.DateTimeField(read_only=True)

    class Meta:
        model = FertilizationPlan
        fields = [
            'id', 'name', 'year', 'variety', 'variety_name', 'crop_name',
-            'calc_settings', 'entries', 'field_count', 'fertilizer_count', 'created_at', 'updated_at'
+            'calc_settings', 'entries', 'field_count', 'fertilizer_count',
+            'is_confirmed', 'confirmed_at', 'created_at', 'updated_at'
        ]

    def get_variety_name(self, obj):
--- a/backend/apps/fertilizer/views.py
+++ b/backend/apps/fertilizer/views.py
@@ -4,12 +4,19 @@ from django.http import HttpResponse
 from django.template.loader import render_to_string
 from rest_framework import viewsets, status
 from rest_framework.decorators import action
+from rest_framework.exceptions import ValidationError
 from rest_framework.permissions import IsAuthenticated
 from rest_framework.response import Response
 from rest_framework.views import APIView
 from weasyprint import HTML

 from apps.fields.models import Field
+from apps.materials.stock_service import (
+    confirm_spreading as confirm_spreading_service,
+    create_reserves_for_plan,
+    delete_reserves_for_plan,
+    unconfirm_spreading,
+)
 from apps.plans.models import Plan, Variety
 from .models import Fertilizer, FertilizationPlan, DistributionPlan
 from .serializers import (
@@ -33,7 +40,7 @@ class FertilizationPlanViewSet(viewsets.ModelViewSet):

    def get_queryset(self):
        qs = FertilizationPlan.objects.select_related('variety', 'variety__crop').prefetch_related(
-            'entries', 'entries__field', 'entries__fertilizer'
+            'entries', 'entries__field', 'entries__fertilizer', 'entries__fertilizer__material'
        )
        year = self.request.query_params.get('year')
        if year:
@@ -45,6 +52,20 @@ class FertilizationPlanViewSet(viewsets.ModelViewSet):
            return FertilizationPlanWriteSerializer
        return FertilizationPlanSerializer

+    def perform_create(self, serializer):
+        instance = serializer.save()
+        create_reserves_for_plan(instance)
+
+    def perform_update(self, serializer):
+        if serializer.instance.is_confirmed:
+            raise ValidationError({'detail': '確定済みの施肥計画は編集できません。'})
+        instance = serializer.save()
+        create_reserves_for_plan(instance)
+
+    def perform_destroy(self, instance):
+        delete_reserves_for_plan(instance)
+        instance.delete()
+
    @action(detail=True, methods=['get'])
    def pdf(self, request, pk=None):
        plan = self.get_object()
@@ -99,6 +120,67 @@ class FertilizationPlanViewSet(viewsets.ModelViewSet):
        response['Content-Disposition'] = f'attachment; filename="fertilization_{plan.year}_{plan.id}.pdf"'
        return response

+    @action(detail=True, methods=['post'], url_path='confirm_spreading')
+    def confirm_spreading(self, request, pk=None):
+        plan = self.get_object()
+
+        if plan.is_confirmed:
+            return Response(
+                {'detail': 'この計画は既に散布確定済みです。'},
+                status=status.HTTP_400_BAD_REQUEST,
+            )
+
+        entries_data = request.data.get('entries', [])
+        if not entries_data:
+            return Response(
+                {'detail': '実績データが空です。'},
+                status=status.HTTP_400_BAD_REQUEST,
+            )
+
+        actual_entries = []
+        for entry in entries_data:
+            field_id = entry.get('field_id')
+            fertilizer_id = entry.get('fertilizer_id')
+            if not field_id or not fertilizer_id:
+                return Response(
+                    {'detail': 'field_id と fertilizer_id が必要です。'},
+                    status=status.HTTP_400_BAD_REQUEST,
+                )
+            try:
+                actual_bags = Decimal(str(entry.get('actual_bags', 0)))
+            except InvalidOperation:
+                return Response(
+                    {'detail': 'actual_bags は数値で指定してください。'},
+                    status=status.HTTP_400_BAD_REQUEST,
+                )
+            actual_entries.append(
+                {
+                    'field_id': field_id,
+                    'fertilizer_id': fertilizer_id,
+                    'actual_bags': actual_bags,
+                }
+            )
+
+        confirm_spreading_service(plan, actual_entries)
+        plan.refresh_from_db()
+        serializer = self.get_serializer(plan)
+        return Response(serializer.data)
+
+    @action(detail=True, methods=['post'], url_path='unconfirm')
+    def unconfirm(self, request, pk=None):
+        plan = self.get_object()
+
+        if not plan.is_confirmed:
+            return Response(
+                {'detail': 'この計画はまだ確定されていません。'},
+                status=status.HTTP_400_BAD_REQUEST,
+            )
+
+        unconfirm_spreading(plan)
+        plan.refresh_from_db()
+        serializer = self.get_serializer(plan)
+        return Response(serializer.data)
+

 class CandidateFieldsView(APIView):
    """作付け計画から圃場候補を返す"""
--- a/backend/apps/materials/init.py
+++ b/backend/apps/materials/init.py
@@ -0,0 +1 @@
+
--- a/backend/apps/materials/admin.py
+++ b/backend/apps/materials/admin.py
@@ -0,0 +1,28 @@
+from django.contrib import admin
+
+from .models import FertilizerProfile, Material, PesticideProfile, StockTransaction
+
+
+class FertilizerProfileInline(admin.StackedInline):
+    model = FertilizerProfile
+    extra = 0
+
+
+class PesticideProfileInline(admin.StackedInline):
+    model = PesticideProfile
+    extra = 0
+
+
+@admin.register(Material)
+class MaterialAdmin(admin.ModelAdmin):
+    list_display = ['name', 'material_type', 'maker', 'stock_unit', 'is_active']
+    list_filter = ['material_type', 'is_active']
+    search_fields = ['name', 'maker']
+    inlines = [FertilizerProfileInline, PesticideProfileInline]
+
+
+@admin.register(StockTransaction)
+class StockTransactionAdmin(admin.ModelAdmin):
+    list_display = ['material', 'transaction_type', 'quantity', 'occurred_on']
+    list_filter = ['transaction_type', 'occurred_on']
+    search_fields = ['material__name']
--- a/backend/apps/materials/apps.py
+++ b/backend/apps/materials/apps.py
@@ -0,0 +1,8 @@
+from django.apps import AppConfig
+
+
+class MaterialsConfig(AppConfig):
+    default_auto_field = 'django.db.models.BigAutoField'
+    name = 'apps.materials'
+    verbose_name = '資材管理'
+
--- a/backend/apps/materials/migrations/0001_initial.py
+++ b/backend/apps/materials/migrations/0001_initial.py
@@ -0,0 +1,87 @@
+import decimal
+
+import django.core.validators
+import django.db.models.deletion
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    initial = True
+
+    dependencies = []
+
+    operations = [
+        migrations.CreateModel(
+            name='Material',
+            fields=[
+                ('id', models.BigAutoField(auto_created=True, primary_key=True, serialize=False, verbose_name='ID')),
+                ('name', models.CharField(max_length=100, verbose_name='資材名')),
+                ('material_type', models.CharField(choices=[('fertilizer', '肥料'), ('pesticide', '農薬'), ('seedling', '種苗'), ('other', 'その他')], max_length=20, verbose_name='資材種別')),
+                ('maker', models.CharField(blank=True, default='', max_length=100, verbose_name='メーカー')),
+                ('stock_unit', models.CharField(choices=[('bag', '袋'), ('bottle', '本'), ('kg', 'kg'), ('liter', 'L'), ('piece', '個')], default='bag', max_length=20, verbose_name='在庫単位')),
+                ('is_active', models.BooleanField(default=True, verbose_name='使用中')),
+                ('notes', models.TextField(blank=True, default='', verbose_name='備考')),
+                ('created_at', models.DateTimeField(auto_now_add=True)),
+                ('updated_at', models.DateTimeField(auto_now=True)),
+            ],
+            options={
+                'verbose_name': '資材',
+                'verbose_name_plural': '資材',
+                'ordering': ['material_type', 'name'],
+            },
+        ),
+        migrations.CreateModel(
+            name='FertilizerProfile',
+            fields=[
+                ('id', models.BigAutoField(auto_created=True, primary_key=True, serialize=False, verbose_name='ID')),
+                ('capacity_kg', models.DecimalField(blank=True, decimal_places=3, max_digits=8, null=True, verbose_name='1袋重量(kg)')),
+                ('nitrogen_pct', models.DecimalField(blank=True, decimal_places=2, max_digits=5, null=True, verbose_name='窒素(%)')),
+                ('phosphorus_pct', models.DecimalField(blank=True, decimal_places=2, max_digits=5, null=True, verbose_name='リン酸(%)')),
+                ('potassium_pct', models.DecimalField(blank=True, decimal_places=2, max_digits=5, null=True, verbose_name='カリ(%)')),
+                ('material', models.OneToOneField(on_delete=django.db.models.deletion.CASCADE, related_name='fertilizer_profile', to='materials.material')),
+            ],
+            options={
+                'verbose_name': '肥料詳細',
+                'verbose_name_plural': '肥料詳細',
+            },
+        ),
+        migrations.CreateModel(
+            name='PesticideProfile',
+            fields=[
+                ('id', models.BigAutoField(auto_created=True, primary_key=True, serialize=False, verbose_name='ID')),
+                ('registration_no', models.CharField(blank=True, default='', max_length=100, verbose_name='農薬登録番号')),
+                ('formulation', models.CharField(blank=True, default='', max_length=100, verbose_name='剤型')),
+                ('usage_unit', models.CharField(blank=True, default='', max_length=50, verbose_name='使用単位')),
+                ('dilution_ratio', models.CharField(blank=True, default='', max_length=100, verbose_name='希釈倍率')),
+                ('active_ingredient', models.CharField(blank=True, default='', max_length=200, verbose_name='有効成分')),
+                ('category', models.CharField(blank=True, default='', max_length=100, verbose_name='分類')),
+                ('material', models.OneToOneField(on_delete=django.db.models.deletion.CASCADE, related_name='pesticide_profile', to='materials.material')),
+            ],
+            options={
+                'verbose_name': '農薬詳細',
+                'verbose_name_plural': '農薬詳細',
+            },
+        ),
+        migrations.CreateModel(
+            name='StockTransaction',
+            fields=[
+                ('id', models.BigAutoField(auto_created=True, primary_key=True, serialize=False, verbose_name='ID')),
+                ('transaction_type', models.CharField(choices=[('purchase', '入庫'), ('use', '使用'), ('adjustment_plus', '棚卸増'), ('adjustment_minus', '棚卸減'), ('discard', '廃棄')], max_length=30, verbose_name='取引種別')),
+                ('quantity', models.DecimalField(decimal_places=3, max_digits=10, validators=[django.core.validators.MinValueValidator(decimal.Decimal('0.001'))], verbose_name='数量')),
+                ('occurred_on', models.DateField(verbose_name='発生日')),
+                ('note', models.TextField(blank=True, default='', verbose_name='備考')),
+                ('created_at', models.DateTimeField(auto_now_add=True)),
+                ('material', models.ForeignKey(on_delete=django.db.models.deletion.PROTECT, related_name='stock_transactions', to='materials.material', verbose_name='資材')),
+            ],
+            options={
+                'verbose_name': '入出庫履歴',
+                'verbose_name_plural': '入出庫履歴',
+                'ordering': ['-occurred_on', '-created_at', '-id'],
+            },
+        ),
+        migrations.AddConstraint(
+            model_name='material',
+            constraint=models.UniqueConstraint(fields=('material_type', 'name'), name='uniq_material_type_name'),
+        ),
+    ]
--- a/backend/apps/materials/migrations/0002_stocktransaction_fertilization_plan.py
+++ b/backend/apps/materials/migrations/0002_stocktransaction_fertilization_plan.py
@@ -0,0 +1,25 @@
+import django.db.models.deletion
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('materials', '0001_initial'),
+        ('fertilizer', '0005_fertilizer_material'),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name='stocktransaction',
+            name='fertilization_plan',
+            field=models.ForeignKey(
+                blank=True,
+                null=True,
+                on_delete=django.db.models.deletion.SET_NULL,
+                related_name='stock_reservations',
+                to='fertilizer.fertilizationplan',
+                verbose_name='施肥計画',
+            ),
+        ),
+    ]
--- a/backend/apps/materials/migrations/init.py
+++ b/backend/apps/materials/migrations/init.py
@@ -0,0 +1 @@
+
--- a/backend/apps/materials/models.py
+++ b/backend/apps/materials/models.py
@@ -0,0 +1,220 @@
+from decimal import Decimal
+
+from django.core.validators import MinValueValidator
+from django.db import models
+
+
+class Material(models.Model):
+    """共通資材マスタ"""
+
+    class MaterialType(models.TextChoices):
+        FERTILIZER = 'fertilizer', '肥料'
+        PESTICIDE = 'pesticide', '農薬'
+        SEEDLING = 'seedling', '種苗'
+        OTHER = 'other', 'その他'
+
+    class StockUnit(models.TextChoices):
+        BAG = 'bag', '袋'
+        BOTTLE = 'bottle', '本'
+        KG = 'kg', 'kg'
+        LITER = 'liter', 'L'
+        PIECE = 'piece', '個'
+
+    name = models.CharField(max_length=100, verbose_name='資材名')
+    material_type = models.CharField(
+        max_length=20,
+        choices=MaterialType.choices,
+        verbose_name='資材種別',
+    )
+    maker = models.CharField(
+        max_length=100,
+        blank=True,
+        default='',
+        verbose_name='メーカー',
+    )
+    stock_unit = models.CharField(
+        max_length=20,
+        choices=StockUnit.choices,
+        default=StockUnit.BAG,
+        verbose_name='在庫単位',
+    )
+    is_active = models.BooleanField(default=True, verbose_name='使用中')
+    notes = models.TextField(blank=True, default='', verbose_name='備考')
+    created_at = models.DateTimeField(auto_now_add=True)
+    updated_at = models.DateTimeField(auto_now=True)
+
+    class Meta:
+        ordering = ['material_type', 'name']
+        constraints = [
+            models.UniqueConstraint(
+                fields=['material_type', 'name'],
+                name='uniq_material_type_name',
+            ),
+        ]
+        verbose_name = '資材'
+        verbose_name_plural = '資材'
+
+    def __str__(self):
+        return f'{self.get_material_type_display()}: {self.name}'
+
+
+class FertilizerProfile(models.Model):
+    """肥料専用属性"""
+
+    material = models.OneToOneField(
+        Material,
+        on_delete=models.CASCADE,
+        related_name='fertilizer_profile',
+    )
+    capacity_kg = models.DecimalField(
+        max_digits=8,
+        decimal_places=3,
+        blank=True,
+        null=True,
+        verbose_name='1袋重量(kg)',
+    )
+    nitrogen_pct = models.DecimalField(
+        max_digits=5,
+        decimal_places=2,
+        blank=True,
+        null=True,
+        verbose_name='窒素(%)',
+    )
+    phosphorus_pct = models.DecimalField(
+        max_digits=5,
+        decimal_places=2,
+        blank=True,
+        null=True,
+        verbose_name='リン酸(%)',
+    )
+    potassium_pct = models.DecimalField(
+        max_digits=5,
+        decimal_places=2,
+        blank=True,
+        null=True,
+        verbose_name='カリ(%)',
+    )
+
+    class Meta:
+        verbose_name = '肥料詳細'
+        verbose_name_plural = '肥料詳細'
+
+    def __str__(self):
+        return f'肥料詳細: {self.material.name}'
+
+
+class PesticideProfile(models.Model):
+    """農薬専用属性"""
+
+    material = models.OneToOneField(
+        Material,
+        on_delete=models.CASCADE,
+        related_name='pesticide_profile',
+    )
+    registration_no = models.CharField(
+        max_length=100,
+        blank=True,
+        default='',
+        verbose_name='農薬登録番号',
+    )
+    formulation = models.CharField(
+        max_length=100,
+        blank=True,
+        default='',
+        verbose_name='剤型',
+    )
+    usage_unit = models.CharField(
+        max_length=50,
+        blank=True,
+        default='',
+        verbose_name='使用単位',
+    )
+    dilution_ratio = models.CharField(
+        max_length=100,
+        blank=True,
+        default='',
+        verbose_name='希釈倍率',
+    )
+    active_ingredient = models.CharField(
+        max_length=200,
+        blank=True,
+        default='',
+        verbose_name='有効成分',
+    )
+    category = models.CharField(
+        max_length=100,
+        blank=True,
+        default='',
+        verbose_name='分類',
+    )
+
+    class Meta:
+        verbose_name = '農薬詳細'
+        verbose_name_plural = '農薬詳細'
+
+    def __str__(self):
+        return f'農薬詳細: {self.material.name}'
+
+
+class StockTransaction(models.Model):
+    """入出庫履歴"""
+
+    class TransactionType(models.TextChoices):
+        PURCHASE = 'purchase', '入庫'
+        USE = 'use', '使用'
+        RESERVE = 'reserve', '引当'
+        ADJUSTMENT_PLUS = 'adjustment_plus', '棚卸増'
+        ADJUSTMENT_MINUS = 'adjustment_minus', '棚卸減'
+        DISCARD = 'discard', '廃棄'
+
+    INCREASE_TYPES = {
+        TransactionType.PURCHASE,
+        TransactionType.ADJUSTMENT_PLUS,
+    }
+    DECREASE_TYPES = {
+        TransactionType.USE,
+        TransactionType.RESERVE,
+        TransactionType.ADJUSTMENT_MINUS,
+        TransactionType.DISCARD,
+    }
+
+    material = models.ForeignKey(
+        Material,
+        on_delete=models.PROTECT,
+        related_name='stock_transactions',
+        verbose_name='資材',
+    )
+    transaction_type = models.CharField(
+        max_length=30,
+        choices=TransactionType.choices,
+        verbose_name='取引種別',
+    )
+    quantity = models.DecimalField(
+        max_digits=10,
+        decimal_places=3,
+        validators=[MinValueValidator(Decimal('0.001'))],
+        verbose_name='数量',
+    )
+    occurred_on = models.DateField(verbose_name='発生日')
+    note = models.TextField(blank=True, default='', verbose_name='備考')
+    fertilization_plan = models.ForeignKey(
+        'fertilizer.FertilizationPlan',
+        on_delete=models.SET_NULL,
+        null=True,
+        blank=True,
+        related_name='stock_reservations',
+        verbose_name='施肥計画',
+    )
+    created_at = models.DateTimeField(auto_now_add=True)
+
+    class Meta:
+        ordering = ['-occurred_on', '-created_at', '-id']
+        verbose_name = '入出庫履歴'
+        verbose_name_plural = '入出庫履歴'
+
+    def __str__(self):
+        return (
+            f'{self.material.name} '
+            f'{self.get_transaction_type_display()} '
+            f'{self.quantity}'
+        )
--- a/backend/apps/materials/serializers.py
+++ b/backend/apps/materials/serializers.py
@@ -0,0 +1,215 @@
+from decimal import Decimal
+
+from django.db import transaction
+from rest_framework import serializers
+
+from .models import (
+    FertilizerProfile,
+    Material,
+    PesticideProfile,
+    StockTransaction,
+)
+
+
+class FertilizerProfileSerializer(serializers.ModelSerializer):
+    class Meta:
+        model = FertilizerProfile
+        fields = ['capacity_kg', 'nitrogen_pct', 'phosphorus_pct', 'potassium_pct']
+
+
+class PesticideProfileSerializer(serializers.ModelSerializer):
+    class Meta:
+        model = PesticideProfile
+        fields = [
+            'registration_no',
+            'formulation',
+            'usage_unit',
+            'dilution_ratio',
+            'active_ingredient',
+            'category',
+        ]
+
+
+class MaterialReadSerializer(serializers.ModelSerializer):
+    material_type_display = serializers.CharField(
+        source='get_material_type_display',
+        read_only=True,
+    )
+    stock_unit_display = serializers.CharField(
+        source='get_stock_unit_display',
+        read_only=True,
+    )
+    fertilizer_profile = FertilizerProfileSerializer(read_only=True)
+    pesticide_profile = PesticideProfileSerializer(read_only=True)
+    current_stock = serializers.SerializerMethodField()
+
+    class Meta:
+        model = Material
+        fields = [
+            'id',
+            'name',
+            'material_type',
+            'material_type_display',
+            'maker',
+            'stock_unit',
+            'stock_unit_display',
+            'is_active',
+            'notes',
+            'fertilizer_profile',
+            'pesticide_profile',
+            'current_stock',
+            'created_at',
+            'updated_at',
+        ]
+
+    def get_current_stock(self, obj):
+        transactions = list(obj.stock_transactions.all())
+        increase = sum(
+            transaction.quantity
+            for transaction in transactions
+            if transaction.transaction_type in StockTransaction.INCREASE_TYPES
+        )
+        decrease = sum(
+            transaction.quantity
+            for transaction in transactions
+            if transaction.transaction_type in StockTransaction.DECREASE_TYPES
+        )
+        return increase - decrease
+
+
+class MaterialWriteSerializer(serializers.ModelSerializer):
+    fertilizer_profile = FertilizerProfileSerializer(required=False, allow_null=True)
+    pesticide_profile = PesticideProfileSerializer(required=False, allow_null=True)
+
+    class Meta:
+        model = Material
+        fields = [
+            'id',
+            'name',
+            'material_type',
+            'maker',
+            'stock_unit',
+            'is_active',
+            'notes',
+            'fertilizer_profile',
+            'pesticide_profile',
+        ]
+
+    def validate(self, attrs):
+        material_type = attrs.get('material_type')
+        if self.instance is not None and material_type is None:
+            material_type = self.instance.material_type
+
+        fertilizer_profile = attrs.get('fertilizer_profile')
+        pesticide_profile = attrs.get('pesticide_profile')
+
+        if material_type == Material.MaterialType.FERTILIZER and pesticide_profile:
+            raise serializers.ValidationError(
+                {'pesticide_profile': '肥料には農薬詳細を設定できません。'}
+            )
+        if material_type == Material.MaterialType.PESTICIDE and fertilizer_profile:
+            raise serializers.ValidationError(
+                {'fertilizer_profile': '農薬には肥料詳細を設定できません。'}
+            )
+        if (
+            material_type in {Material.MaterialType.SEEDLING, Material.MaterialType.OTHER}
+            and (fertilizer_profile or pesticide_profile)
+        ):
+            raise serializers.ValidationError(
+                '種苗・その他には詳細プロファイルを設定できません。'
+            )
+        return attrs
+
+    @transaction.atomic
+    def create(self, validated_data):
+        fertilizer_profile_data = validated_data.pop('fertilizer_profile', None)
+        pesticide_profile_data = validated_data.pop('pesticide_profile', None)
+
+        material = Material.objects.create(**validated_data)
+        self._save_profiles(material, fertilizer_profile_data, pesticide_profile_data)
+        return material
+
+    @transaction.atomic
+    def update(self, instance, validated_data):
+        fertilizer_profile_data = validated_data.pop('fertilizer_profile', None)
+        pesticide_profile_data = validated_data.pop('pesticide_profile', None)
+
+        for attr, value in validated_data.items():
+            setattr(instance, attr, value)
+        instance.save()
+
+        self._save_profiles(instance, fertilizer_profile_data, pesticide_profile_data)
+        return instance
+
+    def to_representation(self, instance):
+        return MaterialReadSerializer(instance, context=self.context).data
+
+    def _save_profiles(self, material, fertilizer_profile_data, pesticide_profile_data):
+        if material.material_type == Material.MaterialType.FERTILIZER:
+            if fertilizer_profile_data is not None:
+                profile, _ = FertilizerProfile.objects.get_or_create(material=material)
+                for attr, value in fertilizer_profile_data.items():
+                    setattr(profile, attr, value)
+                profile.save()
+            PesticideProfile.objects.filter(material=material).delete()
+            return
+
+        if material.material_type == Material.MaterialType.PESTICIDE:
+            if pesticide_profile_data is not None:
+                profile, _ = PesticideProfile.objects.get_or_create(material=material)
+                for attr, value in pesticide_profile_data.items():
+                    setattr(profile, attr, value)
+                profile.save()
+            FertilizerProfile.objects.filter(material=material).delete()
+            return
+
+        FertilizerProfile.objects.filter(material=material).delete()
+        PesticideProfile.objects.filter(material=material).delete()
+
+
+class StockTransactionSerializer(serializers.ModelSerializer):
+    material_name = serializers.CharField(source='material.name', read_only=True)
+    material_type = serializers.CharField(source='material.material_type', read_only=True)
+    stock_unit = serializers.CharField(source='material.stock_unit', read_only=True)
+    stock_unit_display = serializers.CharField(
+        source='material.get_stock_unit_display',
+        read_only=True,
+    )
+    transaction_type_display = serializers.CharField(
+        source='get_transaction_type_display',
+        read_only=True,
+    )
+
+    class Meta:
+        model = StockTransaction
+        fields = [
+            'id',
+            'material',
+            'material_name',
+            'material_type',
+            'transaction_type',
+            'transaction_type_display',
+            'quantity',
+            'stock_unit',
+            'stock_unit_display',
+            'occurred_on',
+            'note',
+            'fertilization_plan',
+            'created_at',
+        ]
+        read_only_fields = ['created_at']
+
+
+class StockSummarySerializer(serializers.Serializer):
+    material_id = serializers.IntegerField()
+    name = serializers.CharField()
+    material_type = serializers.CharField()
+    material_type_display = serializers.CharField()
+    maker = serializers.CharField()
+    stock_unit = serializers.CharField()
+    stock_unit_display = serializers.CharField()
+    is_active = serializers.BooleanField()
+    current_stock = serializers.DecimalField(max_digits=10, decimal_places=3)
+    reserved_stock = serializers.DecimalField(max_digits=10, decimal_places=3)
+    available_stock = serializers.DecimalField(max_digits=10, decimal_places=3)
+    last_transaction_date = serializers.DateField(allow_null=True)
--- a/backend/apps/materials/stock_service.py
+++ b/backend/apps/materials/stock_service.py
@@ -0,0 +1,100 @@
+from decimal import Decimal, InvalidOperation
+
+from django.db import transaction
+from django.utils import timezone
+
+from .models import StockTransaction
+
+
+@transaction.atomic
+def create_reserves_for_plan(plan):
+    """施肥計画の引当を全置換で作り直す。"""
+    StockTransaction.objects.filter(
+        fertilization_plan=plan,
+        transaction_type=StockTransaction.TransactionType.RESERVE,
+    ).delete()
+
+    if plan.is_confirmed:
+        return
+
+    occurred_on = (
+        plan.updated_at.date() if getattr(plan, 'updated_at', None) else timezone.localdate()
+    )
+
+    for entry in plan.entries.select_related('fertilizer__material'):
+        material = getattr(entry.fertilizer, 'material', None)
+        if material is None:
+            continue
+        StockTransaction.objects.create(
+            material=material,
+            transaction_type=StockTransaction.TransactionType.RESERVE,
+            quantity=entry.bags,
+            occurred_on=occurred_on,
+            note=f'施肥計画「{plan.name}」からの引当',
+            fertilization_plan=plan,
+        )
+
+
+@transaction.atomic
+def delete_reserves_for_plan(plan):
+    """施肥計画に紐づく引当のみ削除する。"""
+    StockTransaction.objects.filter(
+        fertilization_plan=plan,
+        transaction_type=StockTransaction.TransactionType.RESERVE,
+    ).delete()
+
+
+@transaction.atomic
+def confirm_spreading(plan, actual_entries):
+    """引当を使用実績へ変換して施肥計画を確定済みにする。"""
+    from apps.fertilizer.models import Fertilizer
+
+    delete_reserves_for_plan(plan)
+
+    for entry_data in actual_entries:
+        actual_bags = _to_decimal(entry_data.get('actual_bags'))
+        if actual_bags <= 0:
+            continue
+
+        fertilizer = (
+            Fertilizer.objects.select_related('material')
+            .filter(id=entry_data['fertilizer_id'])
+            .first()
+        )
+        if fertilizer is None or fertilizer.material is None:
+            continue
+
+        StockTransaction.objects.create(
+            material=fertilizer.material,
+            transaction_type=StockTransaction.TransactionType.USE,
+            quantity=actual_bags,
+            occurred_on=timezone.localdate(),
+            note=f'施肥計画「{plan.name}」散布確定',
+            fertilization_plan=plan,
+        )
+
+    plan.is_confirmed = True
+    plan.confirmed_at = timezone.now()
+    plan.save(update_fields=['is_confirmed', 'confirmed_at'])
+
+
+@transaction.atomic
+def unconfirm_spreading(plan):
+    """散布確定を取り消し、USE トランザクションを削除して引当を再作成する。"""
+    StockTransaction.objects.filter(
+        fertilization_plan=plan,
+        transaction_type=StockTransaction.TransactionType.USE,
+    ).delete()
+
+    plan.is_confirmed = False
+    plan.confirmed_at = None
+    plan.save(update_fields=['is_confirmed', 'confirmed_at'])
+
+    create_reserves_for_plan(plan)
+
+
+def _to_decimal(value):
+    try:
+        return Decimal(str(value))
+    except (InvalidOperation, TypeError, ValueError):
+        return Decimal('0')
--- a/backend/apps/materials/urls.py
+++ b/backend/apps/materials/urls.py
@@ -0,0 +1,18 @@
+from django.urls import include, path
+from rest_framework.routers import DefaultRouter
+
+from . import views
+
+router = DefaultRouter()
+router.register(r'materials', views.MaterialViewSet, basename='material')
+router.register(
+    r'stock-transactions',
+    views.StockTransactionViewSet,
+    basename='stock-transaction',
+)
+
+urlpatterns = [
+    path('', include(router.urls)),
+    path('stock-summary/', views.StockSummaryView.as_view(), name='stock-summary'),
+    path('fertilizer-stock/', views.FertilizerStockView.as_view(), name='fertilizer-stock'),
+]
--- a/backend/apps/materials/views.py
+++ b/backend/apps/materials/views.py
@@ -0,0 +1,164 @@
+from decimal import Decimal
+
+from rest_framework import generics, status, viewsets
+from rest_framework.permissions import IsAuthenticated
+from rest_framework.response import Response
+
+from .models import Material, StockTransaction
+from .serializers import (
+    MaterialReadSerializer,
+    MaterialWriteSerializer,
+    StockSummarySerializer,
+    StockTransactionSerializer,
+)
+
+
+class MaterialViewSet(viewsets.ModelViewSet):
+    """資材マスタ CRUD"""
+
+    permission_classes = [IsAuthenticated]
+
+    def get_queryset(self):
+        queryset = Material.objects.select_related(
+            'fertilizer_profile',
+            'pesticide_profile',
+        ).prefetch_related('stock_transactions')
+
+        material_type = self.request.query_params.get('material_type')
+        if material_type:
+            queryset = queryset.filter(material_type=material_type)
+
+        active = self.request.query_params.get('active')
+        if active is not None:
+            queryset = queryset.filter(is_active=active.lower() == 'true')
+
+        return queryset
+
+    def get_serializer_class(self):
+        if self.action in ['create', 'update', 'partial_update']:
+            return MaterialWriteSerializer
+        return MaterialReadSerializer
+
+    def destroy(self, request, *args, **kwargs):
+        instance = self.get_object()
+        if instance.stock_transactions.exists():
+            return Response(
+                {'detail': 'この資材には入出庫履歴があるため削除できません。無効化してください。'},
+                status=status.HTTP_400_BAD_REQUEST,
+            )
+        return super().destroy(request, *args, **kwargs)
+
+
+class StockTransactionViewSet(viewsets.ModelViewSet):
+    """入出庫履歴 CRUD"""
+
+    serializer_class = StockTransactionSerializer
+    permission_classes = [IsAuthenticated]
+    http_method_names = ['get', 'post', 'delete', 'head', 'options']
+
+    def get_queryset(self):
+        queryset = StockTransaction.objects.select_related('material')
+
+        material_id = self.request.query_params.get('material_id')
+        if material_id:
+            queryset = queryset.filter(material_id=material_id)
+
+        material_type = self.request.query_params.get('material_type')
+        if material_type:
+            queryset = queryset.filter(material__material_type=material_type)
+
+        date_from = self.request.query_params.get('date_from')
+        if date_from:
+            queryset = queryset.filter(occurred_on__gte=date_from)
+
+        date_to = self.request.query_params.get('date_to')
+        if date_to:
+            queryset = queryset.filter(occurred_on__lte=date_to)
+
+        return queryset
+
+
+class StockSummaryView(generics.ListAPIView):
+    """在庫集計一覧"""
+
+    serializer_class = StockSummarySerializer
+    permission_classes = [IsAuthenticated]
+
+    def get_queryset(self):
+        return Material.objects.none()
+
+    def list(self, request, *args, **kwargs):
+        queryset = Material.objects.prefetch_related('stock_transactions').order_by(
+            'material_type',
+            'name',
+        )
+
+        material_type = request.query_params.get('material_type')
+        if material_type:
+            queryset = queryset.filter(material_type=material_type)
+
+        active = request.query_params.get('active')
+        if active is not None:
+            queryset = queryset.filter(is_active=active.lower() == 'true')
+
+        results = []
+        for material in queryset:
+            results.append(_build_stock_summary(material))
+
+        serializer = self.get_serializer(results, many=True)
+        return Response(serializer.data)
+
+
+class FertilizerStockView(generics.ListAPIView):
+    """施肥計画画面用: 肥料の在庫情報を返す"""
+
+    permission_classes = [IsAuthenticated]
+    serializer_class = StockSummarySerializer
+
+    def get_queryset(self):
+        return Material.objects.none()
+
+    def list(self, request, *args, **kwargs):
+        queryset = Material.objects.filter(
+            material_type=Material.MaterialType.FERTILIZER,
+            is_active=True,
+        ).prefetch_related('stock_transactions').order_by('name')
+
+        results = [_build_stock_summary(material) for material in queryset]
+        serializer = self.get_serializer(results, many=True)
+        return Response(serializer.data)
+
+
+def _build_stock_summary(material):
+    transactions = list(material.stock_transactions.all())
+    increase = sum(
+        txn.quantity
+        for txn in transactions
+        if txn.transaction_type in StockTransaction.INCREASE_TYPES
+    )
+    decrease = sum(
+        txn.quantity
+        for txn in transactions
+        if txn.transaction_type in StockTransaction.DECREASE_TYPES
+    )
+    reserved = sum(
+        txn.quantity
+        for txn in transactions
+        if txn.transaction_type == StockTransaction.TransactionType.RESERVE
+    )
+    available = increase - decrease if transactions else Decimal('0')
+    last_date = max((txn.occurred_on for txn in transactions), default=None)
+    return {
+        'material_id': material.id,
+        'name': material.name,
+        'material_type': material.material_type,
+        'material_type_display': material.get_material_type_display(),
+        'maker': material.maker,
+        'stock_unit': material.stock_unit,
+        'stock_unit_display': material.get_stock_unit_display(),
+        'is_active': material.is_active,
+        'current_stock': available + reserved,
+        'reserved_stock': reserved,
+        'available_stock': available,
+        'last_transaction_date': last_date,
+    }
--- a/backend/keinasystem/settings.py
+++ b/backend/keinasystem/settings.py
@@ -44,6 +44,7 @@ INSTALLED_APPS = [
    'apps.mail',
    'apps.weather',
    'apps.fertilizer',
+    'apps.materials',
 ]

 MIDDLEWARE = [
--- a/backend/keinasystem/urls.py
+++ b/backend/keinasystem/urls.py
@@ -58,4 +58,5 @@ urlpatterns = [
    path('api/mail/', include('apps.mail.urls')),
    path('api/weather/', include('apps.weather.urls')),
    path('api/fertilizer/', include('apps.fertilizer.urls')),
+    path('api/materials/', include('apps.materials.urls')),
 ]
--- a/designated_mix_national.zip
+++ b/designated_mix_national.zip
--- a/designated_mix_national/6.
+++ b/designated_mix_national/6.
--- a/document/13_マスタードキュメント_施肥計画編.md
+++ b/document/13_マスタードキュメント_施肥計画編.md
@@ -1,16 +1,16 @@
 # マスタードキュメント：施肥計画機能

 > **作成**: 2026-03-01
-> **最終更新**: 2026-03-01
-> **対象機能**: 施肥計画（年度×品種単位のマトリクス管理）
-> **実装状況**: 実装完了・本番稼働中（最終 commit deb03ef）
+> **最終更新**: 2026-03-15
+> **対象機能**: 施肥計画（年度×品種単位のマトリクス管理・在庫引当・散布確定）
+> **実装状況**: 実装完了・本番稼働中

 ---

 ## 概要

 農業生産者が「年度 × 品種」単位で施肥計画を立てる機能。
-複数圃場 × 複数肥料 × 袋数をマトリクス形式で管理し、PDF出力する。
+複数圃場 × 複数肥料 × 袋数をマトリクス形式で管理し、PDF出力に加えて在庫引当と散布確定まで一連で扱う。

 ### 機能スコープ（IN / OUT）

@@ -18,9 +18,11 @@
 |---|---|
 | 肥料マスタ管理 | 肥料購入管理 |
 | 施肥計画の作成・編集・削除 | 圃場への配置計画（置き場所割り当て） |
-| 3方式の自動計算 | 施肥作業の実績記録 |
+| 3方式の自動計算 | 個別作業日報の詳細管理 |
 | 作付け計画からの圃場自動取得 | |
 | PDF出力（圃場×肥料マトリクス表） | |
+| 在庫引当・引当解除 | |
+| 散布確定（計画値確認 + 実績入力） | |

 ---

@@ -47,6 +49,8 @@
 | name | varchar(200) | required | 計画名（ユーザーが自由入力） |
 | year | int | required | 年度 |
 | variety | FK(plans.Variety) | PROTECT | 品種（≠NULL） |
+| is_confirmed | bool | default=False | 散布確定済みフラグ |
+| confirmed_at | datetime | nullable | 散布確定日時 |
 | created_at | datetime | auto | |
 | updated_at | datetime | auto | |

@@ -102,6 +106,8 @@
 | GET | `/api/fertilizer/plans/{id}/` | 詳細取得（entries 含む） |
 | PUT | `/api/fertilizer/plans/{id}/` | 更新（entries 全置換） |
 | DELETE | `/api/fertilizer/plans/{id}/` | 削除 |
+| POST | `/api/fertilizer/plans/{id}/confirm_spreading/` | 散布確定（引当 → 使用へ変換） |
+| POST | `/api/fertilizer/plans/{id}/unconfirm/` | 散布確定取消（使用 → 引当に戻す） |
 | GET | `/api/fertilizer/plans/{id}/pdf/` | PDF出力（application/pdf） |

 一覧レスポンス例（FertilizationPlan）:
@@ -113,6 +119,8 @@
  "variety": 3,
  "variety_name": "コシヒカリ",
  "crop_name": "米",
+  "is_confirmed": false,
+  "confirmed_at": null,
  "field_count": 12,
  "fertilizer_count": 2,
  "entries": [
@@ -146,6 +154,19 @@ POST/PUT リクエスト例:

 PUT 時は entries が全置換（削除→再作成）。entries を省略した場合は既存を維持。

+散布確定 API リクエスト例:
+```json
+{
+  "entries": [
+    {"field_id": 5, "fertilizer_id": 1, "actual_bags": 2.4},
+    {"field_id": 6, "fertilizer_id": 1, "actual_bags": 0}
+  ]
+}
+```
+
+- `actual_bags > 0`: 対応する引当を使用実績へ変換
+- `actual_bags = 0`: 未散布として引当解除
+
 ### 圃場候補取得

 ```
@@ -269,8 +290,8 @@ GET /api/plans/crops/
 ### 施肥計画一覧（`/fertilizer`）

 - 年度セレクタ（localStorage `fertilizerYear` で保持）
- 計画カード一覧: 計画名・作物/品種・圃場数・肥料数
- 操作ボタン: PDF出力・編集・削除
+- 計画カード一覧: 計画名・作物/品種・圃場数・肥料数・散布確定状態
+- 操作ボタン: PDF出力・編集・削除・散布確定
 - ヘッダー: 「肥料マスタ」「新規作成」ボタン

 ### 肥料マスタ（`/fertilizer/masters`）
@@ -295,6 +316,12 @@ GET /api/plans/crops/
 6. **手動調整**: マトリクス表のセルを直接編集
 7. **保存**: 「保存」ボタンで entries を一括送信

+#### 在庫連携・確定状態
+
+- 肥料列ヘッダーに在庫 / 利用可能在庫 / 計画計 / 不足数を表示
+- 散布確定済みの計画は情報バナーを表示し、編集操作をロック
+- 「確定取消」で使用実績を引当に戻し、再編集できる
+
 #### マトリクスの表示仕様

 - 自動計算直後: セルに計算値（小数）がそのまま表示される（編集可）
@@ -302,6 +329,15 @@ GET /api/plans/crops/
 - `↩` ボタン押下: 整数値を破棄し、元の計算値に戻る（参照グレー表示も消える）
 - 編集中に計算を再実行すると、その肥料列の `adjusted` と `roundedColumns` がリセットされる

+### 散布確定モーダル（`/fertilizer` 一覧から起動）
+
+- 全画面遷移ではなくモーダル表示
+- 施肥計画編集と同じ視線移動になるよう、`圃場 = 行`、`肥料 = 列` のマトリクス表を採用
+- 画面上部に計画名・年度・作物/品種・対象圃場数・肥料数を表示
+- 各セルは「薄いグレーの計画値」+「実績入力欄」の2段表示
+- 行末に圃場ごとの実績合計、表フッターに肥料別合計と総合計を表示
+- `0` を入力したセルは未散布として扱い、対応する引当を解除する
+
 #### State 構成

 ```typescript
--- a/frontend/src/app/fertilizer/_components/ConfirmSpreadingModal.tsx
+++ b/frontend/src/app/fertilizer/_components/ConfirmSpreadingModal.tsx
@@ -0,0 +1,308 @@
+'use client';
+
+import { useEffect, useMemo, useState } from 'react';
+import { Loader2, X } from 'lucide-react';
+
+import { api } from '@/lib/api';
+import { FertilizationPlan } from '@/types';
+
+interface ConfirmSpreadingModalProps {
+  plan: FertilizationPlan | null;
+  isOpen: boolean;
+  onClose: () => void;
+  onConfirmed: () => Promise<void> | void;
+}
+
+type ActualMap = Record<string, string>;
+
+const entryKey = (fieldId: number, fertilizerId: number) => `${fieldId}-${fertilizerId}`;
+type EntryMatrix = Record<number, Record<number, string>>;
+
+export default function ConfirmSpreadingModal({
+  plan,
+  isOpen,
+  onClose,
+  onConfirmed,
+}: ConfirmSpreadingModalProps) {
+  const [actuals, setActuals] = useState<ActualMap>({});
+  const [saving, setSaving] = useState(false);
+  const [error, setError] = useState<string | null>(null);
+
+  useEffect(() => {
+    if (!isOpen || !plan) {
+      return;
+    }
+
+    const nextActuals: ActualMap = {};
+    plan.entries.forEach((entry) => {
+      nextActuals[entryKey(entry.field, entry.fertilizer)] = String(entry.bags);
+    });
+    setActuals(nextActuals);
+    setError(null);
+  }, [isOpen, plan]);
+
+  const layout = useMemo(() => {
+    if (!plan) {
+      return {
+        fields: [] as { id: number; name: string; areaTan: string | undefined }[],
+        fertilizers: [] as { id: number; name: string }[],
+        planned: {} as EntryMatrix,
+      };
+    }
+
+    const fieldMap = new Map<number, { id: number; name: string; areaTan: string | undefined }>();
+    const fertilizerMap = new Map<number, { id: number; name: string }>();
+    const planned: EntryMatrix = {};
+
+    plan.entries.forEach((entry) => {
+      if (!fieldMap.has(entry.field)) {
+        fieldMap.set(entry.field, {
+          id: entry.field,
+          name: entry.field_name ?? `圃場ID:${entry.field}`,
+          areaTan: entry.field_area_tan,
+        });
+      }
+      if (!fertilizerMap.has(entry.fertilizer)) {
+        fertilizerMap.set(entry.fertilizer, {
+          id: entry.fertilizer,
+          name: entry.fertilizer_name ?? `肥料ID:${entry.fertilizer}`,
+        });
+      }
+      if (!planned[entry.field]) {
+        planned[entry.field] = {};
+      }
+      planned[entry.field][entry.fertilizer] = String(entry.bags);
+    });
+
+    return {
+      fields: Array.from(fieldMap.values()),
+      fertilizers: Array.from(fertilizerMap.values()),
+      planned,
+    };
+  }, [plan]);
+
+  if (!isOpen || !plan) {
+    return null;
+  }
+
+  const handleConfirm = async () => {
+    setSaving(true);
+    setError(null);
+
+    try {
+      await api.post(`/fertilizer/plans/${plan.id}/confirm_spreading/`, {
+        entries: plan.entries.map((entry) => ({
+          field_id: entry.field,
+          fertilizer_id: entry.fertilizer,
+          actual_bags: Number(actuals[entryKey(entry.field, entry.fertilizer)] || 0),
+        })),
+      });
+      await onConfirmed();
+      onClose();
+    } catch (e: unknown) {
+      console.error(e);
+      const detail =
+        typeof e === 'object' &&
+        e !== null &&
+        'response' in e &&
+        typeof e.response === 'object' &&
+        e.response !== null &&
+        'data' in e.response
+          ? JSON.stringify(e.response.data)
+          : '散布確定に失敗しました。';
+      setError(detail);
+    } finally {
+      setSaving(false);
+    }
+  };
+
+  const numericValue = (value: string | undefined) => {
+    const parsed = parseFloat(value ?? '0');
+    return isNaN(parsed) ? 0 : parsed;
+  };
+
+  const actualTotalByField = (fieldId: number) =>
+    layout.fertilizers.reduce(
+      (sum, fertilizer) => sum + numericValue(actuals[entryKey(fieldId, fertilizer.id)]),
+      0
+    );
+
+  const actualTotalByFertilizer = (fertilizerId: number) =>
+    layout.fields.reduce(
+      (sum, field) => sum + numericValue(actuals[entryKey(field.id, fertilizerId)]),
+      0
+    );
+
+  return (
+    <div className="fixed inset-0 z-50 flex items-center justify-center bg-gray-900/40 px-4">
+      <div className="max-h-[92vh] w-full max-w-[95vw] overflow-hidden rounded-2xl bg-white shadow-2xl">
+        <div className="flex items-center justify-between border-b border-gray-200 px-6 py-4">
+          <div>
+            <h2 className="text-lg font-semibold text-gray-900">
+              散布確定: 「{plan.name}」
+            </h2>
+            <p className="text-sm text-gray-500">
+              施肥計画編集と同じ並びで、各セルの計画値を確認しながら実績数量を入力します。
+            </p>
+          </div>
+          <button
+            onClick={onClose}
+            className="rounded-full p-2 text-gray-400 transition hover:bg-gray-100 hover:text-gray-600"
+          >
+            <X className="h-5 w-5" />
+          </button>
+        </div>
+
+        <div className="max-h-[calc(92vh-144px)] overflow-y-auto bg-gray-50 px-6 py-5">
+          {error && (
+            <div className="mb-4 rounded-lg border border-red-300 bg-red-50 px-4 py-3 text-sm text-red-700">
+              {error}
+            </div>
+          )}
+
+          <div className="mb-4 rounded-lg bg-white p-4 shadow">
+            <div className="grid gap-3 text-sm text-gray-700 sm:grid-cols-4">
+              <div>
+                <div className="text-xs text-gray-500">年度</div>
+                <div className="font-medium">{plan.year}年度</div>
+              </div>
+              <div>
+                <div className="text-xs text-gray-500">作物 / 品種</div>
+                <div className="font-medium">
+                  {plan.crop_name} / {plan.variety_name}
+                </div>
+              </div>
+              <div>
+                <div className="text-xs text-gray-500">対象圃場</div>
+                <div className="font-medium">{plan.field_count}筆</div>
+              </div>
+              <div>
+                <div className="text-xs text-gray-500">肥料数</div>
+                <div className="font-medium">{plan.fertilizer_count}種</div>
+              </div>
+            </div>
+          </div>
+
+          <div className="mb-3 rounded-lg border border-sky-200 bg-sky-50 px-4 py-3 text-xs text-sky-800">
+            各セルの灰色表示が計画値、入力欄が散布実績です。「0」を入力したセルは未散布として引当解除されます。
+          </div>
+
+          <div className="overflow-x-auto rounded-lg bg-white shadow">
+            <table className="min-w-full text-sm border-collapse">
+              <thead className="bg-gray-50">
+                <tr>
+                  <th className="border border-gray-200 px-4 py-3 text-left font-medium text-gray-700 whitespace-nowrap">
+                    圃場名
+                  </th>
+                  <th className="border border-gray-200 px-3 py-3 text-right font-medium text-gray-700 whitespace-nowrap">
+                    面積(反)
+                  </th>
+                  {layout.fertilizers.map((fertilizer) => (
+                    <th
+                      key={fertilizer.id}
+                      className="border border-gray-200 px-3 py-2 text-center font-medium text-gray-700 whitespace-nowrap"
+                    >
+                      <div>{fertilizer.name}</div>
+                      <div className="mt-0.5 text-[11px] font-normal text-gray-400">
+                        計画 / 実績
+                      </div>
+                    </th>
+                  ))}
+                  <th className="border border-gray-200 px-3 py-3 text-right font-medium text-gray-700 whitespace-nowrap">
+                    実績合計
+                  </th>
+                </tr>
+              </thead>
+              <tbody>
+                {layout.fields.map((field) => (
+                  <tr key={field.id} className="hover:bg-gray-50">
+                    <td className="border border-gray-200 px-4 py-2 whitespace-nowrap text-gray-800">
+                      {field.name}
+                    </td>
+                    <td className="border border-gray-200 px-3 py-2 text-right text-gray-600 whitespace-nowrap">
+                      {field.areaTan ?? '-'}
+                    </td>
+                    {layout.fertilizers.map((fertilizer) => {
+                      const key = entryKey(field.id, fertilizer.id);
+                      const planned = layout.planned[field.id]?.[fertilizer.id];
+                      const hasEntry = planned !== undefined;
+                      return (
+                        <td key={key} className="border border-gray-200 px-2 py-2">
+                          {hasEntry ? (
+                            <div className="flex flex-col items-end gap-1">
+                              <span className="text-[11px] text-gray-400">
+                                計画 {planned}
+                              </span>
+                              <input
+                                type="number"
+                                min="0"
+                                step="0.1"
+                                value={actuals[key] ?? ''}
+                                onChange={(e) =>
+                                  setActuals((prev) => ({
+                                    ...prev,
+                                    [key]: e.target.value,
+                                  }))
+                                }
+                                className="w-20 rounded-md border border-gray-300 px-2 py-1 text-right text-sm focus:border-green-500 focus:outline-none focus:ring-2 focus:ring-green-200"
+                              />
+                            </div>
+                          ) : (
+                            <div className="text-center text-gray-300">-</div>
+                          )}
+                        </td>
+                      );
+                    })}
+                    <td className="border border-gray-200 px-3 py-2 text-right font-medium text-gray-700">
+                      {actualTotalByField(field.id).toFixed(2)}
+                    </td>
+                  </tr>
+                ))}
+              </tbody>
+              <tfoot className="bg-gray-50 font-semibold">
+                <tr>
+                  <td className="border border-gray-200 px-4 py-2">合計</td>
+                  <td className="border border-gray-200 px-3 py-2 text-right text-gray-500">
+                    {layout.fields
+                      .reduce((sum, field) => sum + (parseFloat(field.areaTan ?? '0') || 0), 0)
+                      .toFixed(2)}
+                  </td>
+                  {layout.fertilizers.map((fertilizer) => (
+                    <td
+                      key={fertilizer.id}
+                      className="border border-gray-200 px-3 py-2 text-right text-gray-700"
+                    >
+                      {actualTotalByFertilizer(fertilizer.id).toFixed(2)}
+                    </td>
+                  ))}
+                  <td className="border border-gray-200 px-3 py-2 text-right text-green-700">
+                    {layout.fields
+                      .reduce((sum, field) => sum + actualTotalByField(field.id), 0)
+                      .toFixed(2)}
+                  </td>
+                </tr>
+              </tfoot>
+            </table>
+          </div>
+        </div>
+
+        <div className="flex justify-end gap-3 border-t border-gray-200 px-6 py-4">
+          <button
+            onClick={onClose}
+            className="rounded-lg border border-gray-300 px-4 py-2 text-sm text-gray-700 transition hover:bg-gray-100"
+          >
+            キャンセル
+          </button>
+          <button
+            onClick={handleConfirm}
+            disabled={saving}
+            className="inline-flex items-center gap-2 rounded-lg bg-green-600 px-4 py-2 text-sm font-medium text-white transition hover:bg-green-700 disabled:cursor-not-allowed disabled:opacity-60"
+          >
+            {saving && <Loader2 className="h-4 w-4 animate-spin" />}
+            一括確定
+          </button>
+        </div>
+      </div>
+    </div>
+  );
+}
--- a/frontend/src/app/fertilizer/_components/FertilizerEditPage.tsx
+++ b/frontend/src/app/fertilizer/_components/FertilizerEditPage.tsx
@@ -2,10 +2,10 @@

 import { useState, useEffect, useCallback } from 'react';
 import { useRouter } from 'next/navigation';
-import { ChevronLeft, Plus, X, Calculator, Save, FileDown } from 'lucide-react';
+import { ChevronLeft, Plus, X, Calculator, Save, FileDown, Undo2 } from 'lucide-react';
 import Navbar from '@/components/Navbar';
 import { api } from '@/lib/api';
-import { Fertilizer, FertilizationPlan, Crop, Field } from '@/types';
+import { Crop, FertilizationPlan, Fertilizer, Field, StockSummary } from '@/types';

 type CalcMethod = 'per_tan' | 'even' | 'nitrogen';

@@ -63,6 +63,10 @@ export default function FertilizerEditPage({ planId }: { planId?: number }) {
  const [calcMatrix, setCalcMatrix] = useState<Matrix>({});
  const [adjusted, setAdjusted] = useState<Matrix>({});
  const [roundedColumns, setRoundedColumns] = useState<Set<number>>(new Set());
+  const [stockByMaterialId, setStockByMaterialId] = useState<Record<number, StockSummary>>({});
+  const [initialPlanTotals, setInitialPlanTotals] = useState<Record<number, number>>({});
+  const [isConfirmed, setIsConfirmed] = useState(false);
+  const [confirmedAt, setConfirmedAt] = useState<string | null>(null);

  const [loading, setLoading] = useState(!isNew);
  const [saving, setSaving] = useState(false);
@@ -71,15 +75,26 @@ export default function FertilizerEditPage({ planId }: { planId?: number }) {
  // ─── 初期データ取得
  useEffect(() => {
    const init = async () => {
+      setSaveError(null);
      try {
-        const [cropsRes, fertsRes, fieldsRes] = await Promise.all([
+        const [cropsRes, fertsRes, fieldsRes, stockRes] = await Promise.all([
          api.get('/plans/crops/'),
          api.get('/fertilizer/fertilizers/'),
          api.get('/fields/?ordering=display_order,id'),
+          api.get('/materials/fertilizer-stock/'),
        ]);
        setCrops(cropsRes.data);
        setAllFertilizers(fertsRes.data);
        setAllFields(fieldsRes.data);
+        setStockByMaterialId(
+          stockRes.data.reduce(
+            (acc: Record<number, StockSummary>, summary: StockSummary) => {
+              acc[summary.material_id] = summary;
+              return acc;
+            },
+            {}
+          )
+        );

        if (!isNew && planId) {
          const planRes = await api.get(`/fertilizer/plans/${planId}/`);
@@ -87,6 +102,8 @@ export default function FertilizerEditPage({ planId }: { planId?: number }) {
          setName(plan.name);
          setYear(plan.year);
          setVarietyId(plan.variety);
+          setIsConfirmed(plan.is_confirmed);
+          setConfirmedAt(plan.confirmed_at);

          const fertIds = Array.from(new Set(plan.entries.map((e) => e.fertilizer)));
          const ferts = fertsRes.data.filter((f: Fertilizer) => fertIds.includes(f.id));
@@ -110,6 +127,12 @@ export default function FertilizerEditPage({ planId }: { planId?: number }) {
            newAdjusted[e.field][e.fertilizer] = String(e.bags);
          });
          setAdjusted(newAdjusted);
+          setInitialPlanTotals(
+            plan.entries.reduce((acc: Record<number, number>, entry) => {
+              acc[entry.fertilizer] = (acc[entry.fertilizer] ?? 0) + Number(entry.bags);
+              return acc;
+            }, {})
+          );

          // 保存済み calc_settings でページ開時に自動計算してラベル用 calcMatrix を生成
          const validSettings = plan.calc_settings?.filter((s) => s.param) ?? [];
@@ -142,7 +165,9 @@ export default function FertilizerEditPage({ planId }: { planId?: number }) {
      } catch (e: unknown) {
        const err = e as { response?: { status?: number; data?: unknown } };
        console.error('初期データ取得エラー:', err);
-        alert(`データの読み込みに失敗しました (${err.response?.status ?? 'network error'})\n${JSON.stringify(err.response?.data ?? '')}`);
+        setSaveError(
+          `データの読み込みに失敗しました (${err.response?.status ?? 'network error'}): ${JSON.stringify(err.response?.data ?? '')}`
+        );
      } finally {
        setLoading(false);
      }
@@ -170,6 +195,7 @@ export default function FertilizerEditPage({ planId }: { planId?: number }) {

  // ─── 肥料追加・削除
  const addFertilizer = (fert: Fertilizer) => {
+    if (isConfirmed) return;
    if (planFertilizers.find((f) => f.id === fert.id)) return;
    setPlanFertilizers((prev) => [...prev, fert]);
    setCalcSettings((prev) => [...prev, { fertilizer_id: fert.id, method: 'per_tan', param: '' }]);
@@ -177,6 +203,7 @@ export default function FertilizerEditPage({ planId }: { planId?: number }) {
  };

  const removeFertilizer = (id: number) => {
+    if (isConfirmed) return;
    setPlanFertilizers((prev) => prev.filter((f) => f.id !== id));
    setCalcSettings((prev) => prev.filter((s) => s.fertilizer_id !== id));
    const dropCol = (m: Matrix): Matrix => {
@@ -195,12 +222,14 @@ export default function FertilizerEditPage({ planId }: { planId?: number }) {

  // ─── 圃場追加・削除
  const addField = (field: Field) => {
+    if (isConfirmed) return;
    if (selectedFields.find((f) => f.id === field.id)) return;
    setSelectedFields((prev) => [...prev, field]);
    setShowFieldPicker(false);
  };

  const removeField = (id: number) => {
+    if (isConfirmed) return;
    setSelectedFields((prev) => prev.filter((f) => f.id !== id));
    setCalcMatrix((prev) => { const next = { ...prev }; delete next[id]; return next; });
    setAdjusted((prev) => { const next = { ...prev }; delete next[id]; return next; });
@@ -210,8 +239,16 @@ export default function FertilizerEditPage({ planId }: { planId?: number }) {

  // ─── 自動計算
  const runCalc = async (setting: CalcSetting) => {
-    if (!setting.param) return alert('パラメータを入力してください');
-    if (selectedFields.length === 0) return alert('対象圃場を選択してください');
+    if (isConfirmed) return;
+    if (!setting.param) {
+      setSaveError('パラメータを入力してください');
+      return;
+    }
+    if (selectedFields.length === 0) {
+      setSaveError('対象圃場を選択してください');
+      return;
+    }
+    setSaveError(null);

    const targetFields = calcNewOnly
      ? selectedFields.filter((f) => {
@@ -222,7 +259,10 @@ export default function FertilizerEditPage({ planId }: { planId?: number }) {
        })
      : selectedFields;

-    if (targetFields.length === 0) return alert('未入力の圃場がありません。「全圃場」で実行してください。');
+    if (targetFields.length === 0) {
+      setSaveError('未入力の圃場がありません。「全圃場」で実行してください。');
+      return;
+    }

    try {
      const res = await api.post('/fertilizer/calculate/', {
@@ -246,7 +286,7 @@ export default function FertilizerEditPage({ planId }: { planId?: number }) {
      // adjusted は保持する（テキストボックスにDB/確定値を維持し、ラベルに計算結果を表示）
    } catch (e: unknown) {
      const err = e as { response?: { data?: { error?: string } } };
-      alert(err.response?.data?.error ?? '計算に失敗しました');
+      setSaveError(err.response?.data?.error ?? '計算に失敗しました');
    }
  };

@@ -258,6 +298,7 @@ export default function FertilizerEditPage({ planId }: { planId?: number }) {

  // ─── セル更新（adjusted を更新）
  const updateCell = (fieldId: number, fertId: number, value: string) => {
+    if (isConfirmed) return;
    setAdjusted((prev) => {
      const next = { ...prev };
      if (!next[fieldId]) next[fieldId] = {};
@@ -268,6 +309,7 @@ export default function FertilizerEditPage({ planId }: { planId?: number }) {

  // ─── 列単位で四捨五入 / 元に戻す（トグル）
  const roundColumn = (fertId: number) => {
+    if (isConfirmed) return;
    if (roundedColumns.has(fertId)) {
      // 元に戻す: adjusted からこの列を削除 → calc値が再び表示される
      setAdjusted((prev) => {
@@ -318,10 +360,30 @@ export default function FertilizerEditPage({ planId }: { planId?: number }) {
    selectedFields.reduce((sum, f) => sum + effectiveValue(f.id, fertId), 0);

  const grandTotal = planFertilizers.reduce((sum, f) => sum + colTotal(f.id), 0);
+  const getNumericValue = (value: string | null | undefined) => {
+    const parsed = parseFloat(value ?? '0');
+    return isNaN(parsed) ? 0 : parsed;
+  };
+  const getStockInfo = (fertilizer: Fertilizer) =>
+    fertilizer.material_id ? stockByMaterialId[fertilizer.material_id] ?? null : null;
+  const getPlanAvailableStock = (fertilizer: Fertilizer) => {
+    const stock = getStockInfo(fertilizer);
+    if (!stock) return null;
+    return getNumericValue(stock.available_stock) + (initialPlanTotals[fertilizer.id] ?? 0);
+  };
+  const getPlanShortage = (fertilizer: Fertilizer) => {
+    const available = getPlanAvailableStock(fertilizer);
+    if (available === null) return 0;
+    return Math.max(colTotal(fertilizer.id) - available, 0);
+  };

  // ─── 保存（adjusted 優先、なければ calc 値を使用）
  const handleSave = async () => {
    setSaveError(null);
+    if (isConfirmed) {
+      setSaveError('確定済みの施肥計画は編集できません。');
+      return;
+    }
    if (!name.trim()) { setSaveError('計画名を入力してください'); return; }
    if (!varietyId) { setSaveError('品種を選択してください'); return; }
    if (selectedFields.length === 0) { setSaveError('圃場を1つ以上選択してください'); return; }
@@ -362,9 +424,35 @@ export default function FertilizerEditPage({ planId }: { planId?: number }) {
    }
  };

+  // ─── 確定取消
+  const handleUnconfirm = async () => {
+    if (!planId) return;
+    setSaveError(null);
+    try {
+      await api.post(`/fertilizer/plans/${planId}/unconfirm/`);
+      setIsConfirmed(false);
+      setConfirmedAt(null);
+      // 引当が再作成されるので在庫情報を再取得
+      const stockRes = await api.get('/materials/fertilizer-stock/');
+      setStockByMaterialId(
+        stockRes.data.reduce(
+          (acc: Record<number, StockSummary>, summary: StockSummary) => {
+            acc[summary.material_id] = summary;
+            return acc;
+          },
+          {}
+        )
+      );
+    } catch (e) {
+      console.error(e);
+      setSaveError('確定取消に失敗しました');
+    }
+  };
+
  // ─── PDF出力
  const handlePdf = async () => {
    if (!planId) return;
+    setSaveError(null);
    try {
      const res = await api.get(`/fertilizer/plans/${planId}/pdf/`, { responseType: 'blob' });
      const url = URL.createObjectURL(new Blob([res.data], { type: 'application/pdf' }));
@@ -374,7 +462,8 @@ export default function FertilizerEditPage({ planId }: { planId?: number }) {
      a.click();
      URL.revokeObjectURL(url);
    } catch (e) {
-      alert('PDF出力に失敗しました');
+      console.error(e);
+      setSaveError('PDF出力に失敗しました');
    }
  };

@@ -406,6 +495,15 @@ export default function FertilizerEditPage({ planId }: { planId?: number }) {
            </h1>
          </div>
          <div className="flex items-center gap-2">
+            {!isNew && isConfirmed && (
+              <button
+                onClick={handleUnconfirm}
+                className="flex items-center gap-2 px-4 py-2 border border-amber-300 rounded-lg text-sm text-amber-700 hover:bg-amber-50"
+              >
+                <Undo2 className="h-4 w-4" />
+                確定取消
+              </button>
+            )}
            {!isNew && (
              <button
                onClick={handlePdf}
@@ -417,11 +515,11 @@ export default function FertilizerEditPage({ planId }: { planId?: number }) {
            )}
            <button
              onClick={handleSave}
-              disabled={saving}
-              className="flex items-center gap-2 px-4 py-2 bg-green-600 text-white rounded-lg hover:bg-green-700 disabled:opacity-50"
+              disabled={saving || isConfirmed}
+              className="flex items-center gap-2 px-4 py-2 bg-green-600 text-white rounded-lg hover:bg-green-700 disabled:opacity-50 disabled:cursor-not-allowed"
            >
              <Save className="h-4 w-4" />
-              {saving ? '保存中...' : '保存'}
+              {isConfirmed ? '確定済み' : saving ? '保存中...' : '保存'}
            </button>
          </div>
        </div>
@@ -435,6 +533,16 @@ export default function FertilizerEditPage({ planId }: { planId?: number }) {
          </div>
        )}

+        {isConfirmed && (
+          <div className="mb-4 flex items-start gap-2 bg-sky-50 border border-sky-300 text-sky-800 rounded-lg px-4 py-3 text-sm">
+            <span className="font-bold shrink-0">i</span>
+            <span>
+              この施肥計画は散布確定済みです。
+              {confirmedAt ? ` 確定日時: ${new Date(confirmedAt).toLocaleString('ja-JP')}` : ''}
+            </span>
+          </div>
+        )}
+
        {/* 基本情報 */}
        <div className="bg-white rounded-lg shadow p-4 mb-4 flex flex-wrap gap-4 items-end">
          <div className="flex-1 min-w-48">
@@ -444,6 +552,7 @@ export default function FertilizerEditPage({ planId }: { planId?: number }) {
              value={name}
              onChange={(e) => setName(e.target.value)}
              placeholder="例: 2025年度 コシヒカリ 元肥"
+              disabled={isConfirmed}
            />
          </div>
          <div>
@@ -452,6 +561,7 @@ export default function FertilizerEditPage({ planId }: { planId?: number }) {
              className="border border-gray-300 rounded-lg px-3 py-2 text-sm focus:outline-none focus:ring-2 focus:ring-green-500"
              value={year}
              onChange={(e) => setYear(parseInt(e.target.value))}
+              disabled={isConfirmed}
            >
              {years.map((y) => <option key={y} value={y}>{y}年度</option>)}
            </select>
@@ -462,6 +572,7 @@ export default function FertilizerEditPage({ planId }: { planId?: number }) {
              className="w-full border border-gray-300 rounded-lg px-3 py-2 text-sm focus:outline-none focus:ring-2 focus:ring-green-500"
              value={varietyId}
              onChange={(e) => setVarietyId(e.target.value ? parseInt(e.target.value) : '')}
+              disabled={isConfirmed}
            >
              <option value="">品種を選択</option>
              {crops.map((crop) => (
@@ -487,7 +598,8 @@ export default function FertilizerEditPage({ planId }: { planId?: number }) {
            </h2>
            <button
              onClick={() => setShowFieldPicker(true)}
-              className="flex items-center gap-1 text-xs text-green-600 hover:text-green-800 border border-green-300 rounded px-2 py-1"
+              disabled={isConfirmed}
+              className="flex items-center gap-1 text-xs text-green-600 hover:text-green-800 border border-green-300 rounded px-2 py-1 disabled:opacity-40 disabled:cursor-not-allowed"
            >
              <Plus className="h-3 w-3" />圃場を追加
            </button>
@@ -504,7 +616,11 @@ export default function FertilizerEditPage({ planId }: { planId?: number }) {
                className="flex items-center gap-1 bg-green-50 border border-green-200 rounded-full px-3 py-1 text-xs text-green-800"
              >
                {f.name}（{f.area_tan}反）
-                <button onClick={() => removeField(f.id)} className="text-green-400 hover:text-red-500">
+                <button
+                  onClick={() => removeField(f.id)}
+                  disabled={isConfirmed}
+                  className="text-green-400 hover:text-red-500 disabled:opacity-40 disabled:cursor-not-allowed"
+                >
                  <X className="h-3 w-3" />
                </button>
              </span>
@@ -522,13 +638,15 @@ export default function FertilizerEditPage({ planId }: { planId?: number }) {
                  type="checkbox"
                  checked={calcNewOnly}
                  onChange={(e) => setCalcNewOnly(e.target.checked)}
+                  disabled={isConfirmed}
                  className="rounded border-gray-300 text-blue-600 focus:ring-blue-500"
                />
                未入力圃場のみ
              </label>
              <button
                onClick={() => setShowFertPicker(true)}
-                className="flex items-center gap-1 text-xs text-green-600 hover:text-green-800 border border-green-300 rounded px-2 py-1"
+                disabled={isConfirmed}
+                className="flex items-center gap-1 text-xs text-green-600 hover:text-green-800 border border-green-300 rounded px-2 py-1 disabled:opacity-40 disabled:cursor-not-allowed"
              >
                <Plus className="h-3 w-3" />肥料を追加
              </button>
@@ -550,6 +668,7 @@ export default function FertilizerEditPage({ planId }: { planId?: number }) {
                      className="border border-gray-300 rounded px-2 py-1 text-xs"
                      value={setting.method}
                      onChange={(e) => updateCalcSetting(fert.id, 'method', e.target.value)}
+                      disabled={isConfirmed}
                    >
                      {Object.entries(METHOD_LABELS).map(([k, v]) => (
                        <option key={k} value={k}>{v}</option>
@@ -562,17 +681,20 @@ export default function FertilizerEditPage({ planId }: { planId?: number }) {
                      value={setting.param}
                      onChange={(e) => updateCalcSetting(fert.id, 'param', e.target.value)}
                      placeholder="値"
+                      disabled={isConfirmed}
                    />
                    <span className="text-xs text-gray-500 w-24">{METHOD_UNIT[setting.method]}</span>
                    <button
                      onClick={() => runCalc(setting)}
-                      className="flex items-center gap-1 text-xs bg-blue-50 border border-blue-300 text-blue-700 rounded px-3 py-1 hover:bg-blue-100"
+                      disabled={isConfirmed}
+                      className="flex items-center gap-1 text-xs bg-blue-50 border border-blue-300 text-blue-700 rounded px-3 py-1 hover:bg-blue-100 disabled:opacity-40 disabled:cursor-not-allowed"
                    >
                      <Calculator className="h-3 w-3" />計算
                    </button>
                    <button
                      onClick={() => removeFertilizer(fert.id)}
-                      className="ml-auto text-gray-300 hover:text-red-500"
+                      disabled={isConfirmed}
+                      className="ml-auto text-gray-300 hover:text-red-500 disabled:opacity-40 disabled:cursor-not-allowed"
                    >
                      <X className="h-4 w-4" />
                    </button>
@@ -593,18 +715,44 @@ export default function FertilizerEditPage({ planId }: { planId?: number }) {
                  <th className="text-right px-3 py-3 border border-gray-200 font-medium text-gray-700 whitespace-nowrap">面積(反)</th>
                  {planFertilizers.map((f) => {
                    const isRounded = roundedColumns.has(f.id);
+                    const stock = getStockInfo(f);
+                    const planAvailable = getPlanAvailableStock(f);
+                    const shortage = getPlanShortage(f);
                    return (
                      <th key={f.id} className="text-center px-3 py-2 border border-gray-200 font-medium text-gray-700 whitespace-nowrap">
-                        {f.name}
+                        <div>{f.name}</div>
+                        {stock ? (
+                          <div className="mt-1 space-y-0.5 text-[11px] font-normal leading-4">
+                            <div className="text-gray-500">
+                              在庫 {stock.current_stock}{stock.stock_unit_display}
+                              {planAvailable !== null && (
+                                <span className="ml-1">
+                                  / 利用可能 {planAvailable.toFixed(2)}{stock.stock_unit_display}
+                                </span>
+                              )}
+                            </div>
+                            <div className={shortage > 0 ? 'text-red-600' : 'text-gray-500'}>
+                              計画計 {colTotal(f.id).toFixed(2)}{stock.stock_unit_display}
+                              {shortage > 0 && (
+                                <span className="ml-1">/ 不足 {shortage.toFixed(2)}{stock.stock_unit_display}</span>
+                              )}
+                            </div>
+                          </div>
+                        ) : (
+                          <div className="mt-1 text-[11px] font-normal text-amber-600">
+                            在庫情報なし
+                          </div>
+                        )}
                        <span className="flex items-center justify-center gap-1.5 text-xs font-normal text-gray-400 mt-0.5">
                          （袋）
                          <button
                            onClick={() => roundColumn(f.id)}
+                            disabled={isConfirmed}
                            className={`inline-flex items-center justify-center w-5 h-5 rounded font-bold leading-none ${
                              isRounded
                                ? 'bg-amber-100 text-amber-600 hover:bg-amber-200'
                                : 'bg-blue-100 text-blue-500 hover:bg-blue-200'
-                            }`}
+                            } disabled:opacity-40 disabled:cursor-not-allowed`}
                            title={isRounded ? '元の計算値に戻す' : '四捨五入して整数に丸める'}
                          >
                            {isRounded ? '↩' : '≈'}
@@ -641,6 +789,7 @@ export default function FertilizerEditPage({ planId }: { planId?: number }) {
                              value={inputValue}
                              onChange={(e) => updateCell(field.id, fert.id, e.target.value)}
                              placeholder="-"
+                              disabled={isConfirmed}
                            />
                          </div>
                        </td>
@@ -689,7 +838,8 @@ export default function FertilizerEditPage({ planId }: { planId?: number }) {
                    <button
                      key={f.id}
                      onClick={() => addField(f)}
-                      className="w-full text-left px-3 py-2 hover:bg-green-50 rounded text-sm flex justify-between"
+                      disabled={isConfirmed}
+                      className="w-full text-left px-3 py-2 hover:bg-green-50 rounded text-sm flex justify-between disabled:opacity-40 disabled:cursor-not-allowed"
                    >
                      <span>{f.name}</span>
                      <span className="text-gray-400">{f.area_tan}反</span>
@@ -703,7 +853,8 @@ export default function FertilizerEditPage({ planId }: { planId?: number }) {
                <button
                  key={f.id}
                  onClick={() => addField(f)}
-                  className="w-full text-left px-3 py-2 hover:bg-gray-50 rounded text-sm flex justify-between"
+                  disabled={isConfirmed}
+                  className="w-full text-left px-3 py-2 hover:bg-gray-50 rounded text-sm flex justify-between disabled:opacity-40 disabled:cursor-not-allowed"
                >
                  <span>{f.name}</span>
                  <span className="text-gray-400">{f.area_tan}反</span>
@@ -730,7 +881,8 @@ export default function FertilizerEditPage({ planId }: { planId?: number }) {
                  <button
                    key={f.id}
                    onClick={() => addFertilizer(f)}
-                    className="w-full text-left px-3 py-2 hover:bg-green-50 rounded text-sm"
+                    disabled={isConfirmed}
+                    className="w-full text-left px-3 py-2 hover:bg-green-50 rounded text-sm disabled:opacity-40 disabled:cursor-not-allowed"
                  >
                    <span className="font-medium">{f.name}</span>
                    {f.maker && <span className="ml-2 text-gray-400 text-xs">{f.maker}</span>}
--- a/frontend/src/app/fertilizer/masters/page.tsx
+++ b/frontend/src/app/fertilizer/masters/page.tsx
@@ -15,6 +15,8 @@ const emptyForm = (): Omit<Fertilizer, 'id'> => ({
  phosphorus_pct: null,
  potassium_pct: null,
  notes: null,
+  material: null,
+  material_id: null,
 });

 export default function FertilizerMastersPage() {
@@ -55,6 +57,8 @@ export default function FertilizerMastersPage() {
      phosphorus_pct: f.phosphorus_pct,
      potassium_pct: f.potassium_pct,
      notes: f.notes,
+      material: f.material,
+      material_id: f.material_id,
    });
    setEditingId(f.id);
  };
--- a/frontend/src/app/fertilizer/page.tsx
+++ b/frontend/src/app/fertilizer/page.tsx
@@ -2,7 +2,9 @@

 import { useState, useEffect } from 'react';
 import { useRouter } from 'next/navigation';
-import { Plus, Pencil, Trash2, FileDown, Sprout } from 'lucide-react';
+import { Plus, Pencil, Trash2, FileDown, Sprout, BadgeCheck, Undo2 } from 'lucide-react';
+
+import ConfirmSpreadingModal from './_components/ConfirmSpreadingModal';
 import Navbar from '@/components/Navbar';
 import { api } from '@/lib/api';
 import { FertilizationPlan } from '@/types';
@@ -21,6 +23,8 @@ export default function FertilizerPage() {
  const [plans, setPlans] = useState<FertilizationPlan[]>([]);
  const [loading, setLoading] = useState(true);
  const [deleteError, setDeleteError] = useState<string | null>(null);
+  const [actionError, setActionError] = useState<string | null>(null);
+  const [confirmTarget, setConfirmTarget] = useState<FertilizationPlan | null>(null);

  useEffect(() => {
    localStorage.setItem('fertilizerYear', String(year));
@@ -41,6 +45,7 @@ export default function FertilizerPage() {

  const handleDelete = async (id: number, name: string) => {
    setDeleteError(null);
+    setActionError(null);
    try {
      await api.delete(`/fertilizer/plans/${id}/`);
      await fetchPlans();
@@ -50,7 +55,19 @@ export default function FertilizerPage() {
    }
  };

+  const handleUnconfirm = async (id: number, name: string) => {
+    setActionError(null);
+    try {
+      await api.post(`/fertilizer/plans/${id}/unconfirm/`);
+      await fetchPlans();
+    } catch (e) {
+      console.error(e);
+      setActionError(`「${name}」の確定取消に失敗しました`);
+    }
+  };
+
  const handlePdf = async (id: number, name: string) => {
+    setActionError(null);
    try {
      const res = await api.get(`/fertilizer/plans/${id}/pdf/`, { responseType: 'blob' });
      const url = URL.createObjectURL(new Blob([res.data], { type: 'application/pdf' }));
@@ -61,7 +78,7 @@ export default function FertilizerPage() {
      URL.revokeObjectURL(url);
    } catch (e) {
      console.error(e);
-      alert('PDF出力に失敗しました');
+      setActionError('PDF出力に失敗しました');
    }
  };

@@ -115,6 +132,14 @@ export default function FertilizerPage() {
          </div>
        )}

+        {actionError && (
+          <div className="mb-4 flex items-start gap-2 bg-red-50 border border-red-300 text-red-700 rounded-lg px-4 py-3 text-sm">
+            <span className="font-bold shrink-0">⚠</span>
+            <span>{actionError}</span>
+            <button onClick={() => setActionError(null)} className="ml-auto shrink-0 text-red-400 hover:text-red-600">✕</button>
+          </div>
+        )}
+
        {loading ? (
          <p className="text-gray-500">読み込み中...</p>
        ) : plans.length === 0 ? (
@@ -135,6 +160,7 @@ export default function FertilizerPage() {
                <tr>
                  <th className="text-left px-4 py-3 font-medium text-gray-700">計画名</th>
                  <th className="text-left px-4 py-3 font-medium text-gray-700">作物 / 品種</th>
+                  <th className="text-left px-4 py-3 font-medium text-gray-700">状態</th>
                  <th className="text-right px-4 py-3 font-medium text-gray-700">圃場数</th>
                  <th className="text-right px-4 py-3 font-medium text-gray-700">肥料種数</th>
                  <th className="px-4 py-3"></th>
@@ -142,15 +168,52 @@ export default function FertilizerPage() {
              </thead>
              <tbody className="divide-y divide-gray-100">
                {plans.map((plan) => (
-                  <tr key={plan.id} className="hover:bg-gray-50">
-                    <td className="px-4 py-3 font-medium">{plan.name}</td>
+                  <tr
+                    key={plan.id}
+                    className={plan.is_confirmed ? 'bg-sky-50 hover:bg-sky-100/60' : 'hover:bg-gray-50'}
+                  >
+                    <td className="px-4 py-3 font-medium">
+                      <div className="flex items-center gap-2">
+                        <span>{plan.name}</span>
+                        {plan.is_confirmed && (
+                          <span className="inline-flex items-center gap-1 rounded-full bg-sky-100 px-2 py-0.5 text-xs text-sky-700">
+                            <BadgeCheck className="h-3.5 w-3.5" />
+                            確定済み
+                          </span>
+                        )}
+                      </div>
+                    </td>
                    <td className="px-4 py-3 text-gray-600">
                      {plan.crop_name} / {plan.variety_name}
                    </td>
+                    <td className="px-4 py-3 text-gray-600">
+                      {plan.is_confirmed
+                        ? `散布確定 ${plan.confirmed_at ? new Date(plan.confirmed_at).toLocaleString('ja-JP') : ''}`
+                        : '未確定'}
+                    </td>
                    <td className="px-4 py-3 text-right text-gray-600">{plan.field_count}筆</td>
                    <td className="px-4 py-3 text-right text-gray-600">{plan.fertilizer_count}種</td>
                    <td className="px-4 py-3">
                      <div className="flex items-center gap-2 justify-end">
+                        {!plan.is_confirmed ? (
+                          <button
+                            onClick={() => setConfirmTarget(plan)}
+                            className="flex items-center gap-1 px-2.5 py-1.5 text-xs border border-emerald-300 rounded hover:bg-emerald-50 text-emerald-700"
+                            title="散布確定"
+                          >
+                            <BadgeCheck className="h-3.5 w-3.5" />
+                            散布確定
+                          </button>
+                        ) : (
+                          <button
+                            onClick={() => handleUnconfirm(plan.id, plan.name)}
+                            className="flex items-center gap-1 px-2.5 py-1.5 text-xs border border-amber-300 rounded hover:bg-amber-50 text-amber-700"
+                            title="確定取消"
+                          >
+                            <Undo2 className="h-3.5 w-3.5" />
+                            確定取消
+                          </button>
+                        )}
                        <button
                          onClick={() => handlePdf(plan.id, plan.name)}
                          className="flex items-center gap-1 px-2.5 py-1.5 text-xs border border-gray-300 rounded hover:bg-gray-100 text-gray-700"
@@ -184,6 +247,13 @@ export default function FertilizerPage() {
          </div>
        )}
      </div>
+
+      <ConfirmSpreadingModal
+        isOpen={confirmTarget !== null}
+        plan={confirmTarget}
+        onClose={() => setConfirmTarget(null)}
+        onConfirmed={fetchPlans}
+      />
    </div>
  );
 }
--- a/frontend/src/app/materials/_components/MaterialForm.tsx
+++ b/frontend/src/app/materials/_components/MaterialForm.tsx
@@ -0,0 +1,341 @@
+'use client';
+
+import { Check, X } from 'lucide-react';
+
+import { Material } from '@/types';
+
+export type MaterialTab = 'fertilizer' | 'pesticide' | 'misc';
+
+export interface MaterialFormState {
+  name: string;
+  material_type: Material['material_type'];
+  maker: string;
+  stock_unit: Material['stock_unit'];
+  is_active: boolean;
+  notes: string;
+  fertilizer_profile: {
+    capacity_kg: string;
+    nitrogen_pct: string;
+    phosphorus_pct: string;
+    potassium_pct: string;
+  };
+  pesticide_profile: {
+    registration_no: string;
+    formulation: string;
+    usage_unit: string;
+    dilution_ratio: string;
+    active_ingredient: string;
+    category: string;
+  };
+}
+
+interface MaterialFormProps {
+  tab: MaterialTab;
+  form: MaterialFormState;
+  saving: boolean;
+  onBaseFieldChange: (
+    field: keyof Omit<MaterialFormState, 'fertilizer_profile' | 'pesticide_profile'>,
+    value: string | boolean
+  ) => void;
+  onFertilizerFieldChange: (
+    field: keyof MaterialFormState['fertilizer_profile'],
+    value: string
+  ) => void;
+  onPesticideFieldChange: (
+    field: keyof MaterialFormState['pesticide_profile'],
+    value: string
+  ) => void;
+  onSave: () => void;
+  onCancel: () => void;
+}
+
+const inputClassName =
+  'w-full rounded-md border border-gray-300 px-2 py-1 text-sm focus:border-green-500 focus:outline-none focus:ring-1 focus:ring-green-500';
+
+export default function MaterialForm({
+  tab,
+  form,
+  saving,
+  onBaseFieldChange,
+  onFertilizerFieldChange,
+  onPesticideFieldChange,
+  onSave,
+  onCancel,
+}: MaterialFormProps) {
+  if (tab === 'fertilizer') {
+    return (
+      <tr className="bg-green-50">
+        <td className="px-2 py-2">
+          <input
+            className={inputClassName}
+            value={form.name}
+            onChange={(e) => onBaseFieldChange('name', e.target.value)}
+            placeholder="資材名"
+            autoFocus
+          />
+        </td>
+        <td className="px-2 py-2">
+          <input
+            className={inputClassName}
+            value={form.maker}
+            onChange={(e) => onBaseFieldChange('maker', e.target.value)}
+            placeholder="メーカー"
+          />
+        </td>
+        <td className="px-2 py-2">
+          <input
+            className={inputClassName}
+            type="number"
+            step="0.001"
+            value={form.fertilizer_profile.capacity_kg}
+            onChange={(e) => onFertilizerFieldChange('capacity_kg', e.target.value)}
+            placeholder="kg"
+          />
+        </td>
+        <td className="px-2 py-2">
+          <input
+            className={inputClassName}
+            type="number"
+            step="0.01"
+            value={form.fertilizer_profile.nitrogen_pct}
+            onChange={(e) => onFertilizerFieldChange('nitrogen_pct', e.target.value)}
+            placeholder="%"
+          />
+        </td>
+        <td className="px-2 py-2">
+          <input
+            className={inputClassName}
+            type="number"
+            step="0.01"
+            value={form.fertilizer_profile.phosphorus_pct}
+            onChange={(e) => onFertilizerFieldChange('phosphorus_pct', e.target.value)}
+            placeholder="%"
+          />
+        </td>
+        <td className="px-2 py-2">
+          <input
+            className={inputClassName}
+            type="number"
+            step="0.01"
+            value={form.fertilizer_profile.potassium_pct}
+            onChange={(e) => onFertilizerFieldChange('potassium_pct', e.target.value)}
+            placeholder="%"
+          />
+        </td>
+        <td className="px-2 py-2">
+          <StockUnitSelect
+            value={form.stock_unit}
+            onChange={(value) => onBaseFieldChange('stock_unit', value)}
+          />
+        </td>
+        <td className="px-2 py-2">
+          <input
+            className={inputClassName}
+            value={form.notes}
+            onChange={(e) => onBaseFieldChange('notes', e.target.value)}
+            placeholder="備考"
+          />
+        </td>
+        <td className="px-2 py-2 text-center">
+          <input
+            type="checkbox"
+            checked={form.is_active}
+            onChange={(e) => onBaseFieldChange('is_active', e.target.checked)}
+            className="h-4 w-4 rounded border-gray-300 text-green-600 focus:ring-green-500"
+          />
+        </td>
+        <td className="px-2 py-2">
+          <ActionButtons onSave={onSave} onCancel={onCancel} saving={saving} />
+        </td>
+      </tr>
+    );
+  }
+
+  if (tab === 'pesticide') {
+    return (
+      <tr className="bg-green-50">
+        <td className="px-2 py-2">
+          <input
+            className={inputClassName}
+            value={form.name}
+            onChange={(e) => onBaseFieldChange('name', e.target.value)}
+            placeholder="資材名"
+            autoFocus
+          />
+        </td>
+        <td className="px-2 py-2">
+          <input
+            className={inputClassName}
+            value={form.maker}
+            onChange={(e) => onBaseFieldChange('maker', e.target.value)}
+            placeholder="メーカー"
+          />
+        </td>
+        <td className="px-2 py-2">
+          <input
+            className={inputClassName}
+            value={form.pesticide_profile.registration_no}
+            onChange={(e) => onPesticideFieldChange('registration_no', e.target.value)}
+            placeholder="登録番号"
+          />
+        </td>
+        <td className="px-2 py-2">
+          <input
+            className={inputClassName}
+            value={form.pesticide_profile.formulation}
+            onChange={(e) => onPesticideFieldChange('formulation', e.target.value)}
+            placeholder="剤型"
+          />
+        </td>
+        <td className="px-2 py-2">
+          <input
+            className={inputClassName}
+            value={form.pesticide_profile.active_ingredient}
+            onChange={(e) => onPesticideFieldChange('active_ingredient', e.target.value)}
+            placeholder="有効成分"
+          />
+        </td>
+        <td className="px-2 py-2">
+          <input
+            className={inputClassName}
+            value={form.pesticide_profile.category}
+            onChange={(e) => onPesticideFieldChange('category', e.target.value)}
+            placeholder="分類"
+          />
+        </td>
+        <td className="px-2 py-2">
+          <StockUnitSelect
+            value={form.stock_unit}
+            onChange={(value) => onBaseFieldChange('stock_unit', value)}
+          />
+        </td>
+        <td className="px-2 py-2">
+          <input
+            className={inputClassName}
+            value={form.notes}
+            onChange={(e) => onBaseFieldChange('notes', e.target.value)}
+            placeholder="備考"
+          />
+        </td>
+        <td className="px-2 py-2 text-center">
+          <input
+            type="checkbox"
+            checked={form.is_active}
+            onChange={(e) => onBaseFieldChange('is_active', e.target.checked)}
+            className="h-4 w-4 rounded border-gray-300 text-green-600 focus:ring-green-500"
+          />
+        </td>
+        <td className="px-2 py-2">
+          <ActionButtons onSave={onSave} onCancel={onCancel} saving={saving} />
+        </td>
+      </tr>
+    );
+  }
+
+  return (
+    <tr className="bg-green-50">
+      <td className="px-2 py-2">
+        <input
+          className={inputClassName}
+          value={form.name}
+          onChange={(e) => onBaseFieldChange('name', e.target.value)}
+          placeholder="資材名"
+          autoFocus
+        />
+      </td>
+      <td className="px-2 py-2">
+        <select
+          className={inputClassName}
+          value={form.material_type}
+          onChange={(e) => onBaseFieldChange('material_type', e.target.value)}
+        >
+          <option value="other">その他</option>
+          <option value="seedling">種苗</option>
+        </select>
+      </td>
+      <td className="px-2 py-2">
+        <input
+          className={inputClassName}
+          value={form.maker}
+          onChange={(e) => onBaseFieldChange('maker', e.target.value)}
+          placeholder="メーカー"
+        />
+      </td>
+      <td className="px-2 py-2">
+        <StockUnitSelect
+          value={form.stock_unit}
+          onChange={(value) => onBaseFieldChange('stock_unit', value)}
+        />
+      </td>
+      <td className="px-2 py-2">
+        <input
+          className={inputClassName}
+          value={form.notes}
+          onChange={(e) => onBaseFieldChange('notes', e.target.value)}
+          placeholder="備考"
+        />
+      </td>
+      <td className="px-2 py-2 text-center">
+        <input
+          type="checkbox"
+          checked={form.is_active}
+          onChange={(e) => onBaseFieldChange('is_active', e.target.checked)}
+          className="h-4 w-4 rounded border-gray-300 text-green-600 focus:ring-green-500"
+        />
+      </td>
+      <td className="px-2 py-2">
+        <ActionButtons onSave={onSave} onCancel={onCancel} saving={saving} />
+      </td>
+    </tr>
+  );
+}
+
+function ActionButtons({
+  onSave,
+  onCancel,
+  saving,
+}: {
+  onSave: () => void;
+  onCancel: () => void;
+  saving: boolean;
+}) {
+  return (
+    <div className="flex items-center justify-end gap-1">
+      <button
+        onClick={onSave}
+        disabled={saving}
+        className="text-green-600 transition hover:text-green-800 disabled:opacity-50"
+      >
+        <Check className="h-4 w-4" />
+      </button>
+      <button
+        onClick={onCancel}
+        className="text-gray-400 transition hover:text-gray-600"
+      >
+        <X className="h-4 w-4" />
+      </button>
+    </div>
+  );
+}
+
+function StockUnitSelect({
+  value,
+  onChange,
+}: {
+  value: Material['stock_unit'];
+  onChange: (value: Material['stock_unit']) => void;
+}) {
+  return (
+    <select
+      className={inputClassName}
+      value={value}
+      onChange={(e) => onChange(e.target.value as Material['stock_unit'])}
+    >
+      <option value="bag">袋</option>
+      <option value="bottle">本</option>
+      <option value="kg">kg</option>
+      <option value="liter">L</option>
+      <option value="piece">個</option>
+    </select>
+  );
+}
--- a/frontend/src/app/materials/_components/StockOverview.tsx
+++ b/frontend/src/app/materials/_components/StockOverview.tsx
@@ -0,0 +1,167 @@
+'use client';
+
+import { Fragment } from 'react';
+import { Clock3, Download, Upload } from 'lucide-react';
+
+import { StockSummary, StockTransaction } from '@/types';
+
+interface StockOverviewProps {
+  loading: boolean;
+  items: StockSummary[];
+  expandedMaterialId: number | null;
+  historyLoadingId: number | null;
+  histories: Record<number, StockTransaction[]>;
+  onOpenTransaction: (
+    materialId: number,
+    transactionType: StockTransaction['transaction_type']
+  ) => void;
+  onToggleHistory: (materialId: number) => void;
+}
+
+export default function StockOverview({
+  loading,
+  items,
+  expandedMaterialId,
+  historyLoadingId,
+  histories,
+  onOpenTransaction,
+  onToggleHistory,
+}: StockOverviewProps) {
+  if (loading) {
+    return <p className="text-sm text-gray-500">読み込み中...</p>;
+  }
+
+  if (items.length === 0) {
+    return (
+      <div className="rounded-2xl border border-dashed border-gray-300 bg-white px-6 py-12 text-center text-gray-500">
+        表示できる在庫データがありません。
+      </div>
+    );
+  }
+
+  return (
+    <div className="overflow-hidden rounded-2xl border border-gray-200 bg-white shadow-sm">
+      <table className="w-full text-sm">
+        <thead className="bg-gray-50">
+          <tr className="border-b border-gray-200">
+            <th className="px-4 py-3 text-left font-medium text-gray-700">資材名</th>
+            <th className="px-4 py-3 text-left font-medium text-gray-700">種別</th>
+            <th className="px-4 py-3 text-left font-medium text-gray-700">メーカー</th>
+            <th className="px-4 py-3 text-right font-medium text-gray-700">現在庫</th>
+            <th className="px-4 py-3 text-left font-medium text-gray-700">単位</th>
+            <th className="px-4 py-3 text-left font-medium text-gray-700">最終入出庫日</th>
+            <th className="px-4 py-3 text-right font-medium text-gray-700">操作</th>
+          </tr>
+        </thead>
+        <tbody className="divide-y divide-gray-100">
+          {items.map((item) => {
+            const isExpanded = expandedMaterialId === item.material_id;
+            const history = histories[item.material_id] ?? [];
+
+            return (
+              <Fragment key={item.material_id}>
+                <tr className="hover:bg-gray-50">
+                  <td className="px-4 py-3 font-medium text-gray-900">
+                    <div className="flex items-center gap-2">
+                      <span>{item.name}</span>
+                      {!item.is_active && (
+                        <span className="rounded-full bg-gray-100 px-2 py-0.5 text-xs text-gray-500">
+                          無効
+                        </span>
+                      )}
+                    </div>
+                  </td>
+                  <td className="px-4 py-3 text-gray-600">{item.material_type_display}</td>
+                  <td className="px-4 py-3 text-gray-600">{item.maker || '-'}</td>
+                  <td className="px-4 py-3 text-right">
+                    <div className="font-semibold text-gray-900">
+                      在庫 {item.current_stock}
+                      {item.reserved_stock !== '0.000' && (
+                        <span className="ml-1 text-xs font-normal text-amber-600">
+                          （引当 {item.reserved_stock}）
+                        </span>
+                      )}
+                    </div>
+                    <div className="text-xs text-gray-500">
+                      利用可能 {item.available_stock}
+                    </div>
+                  </td>
+                  <td className="px-4 py-3 text-gray-600">{item.stock_unit_display}</td>
+                  <td className="px-4 py-3 text-gray-600">
+                    {item.last_transaction_date ?? '-'}
+                  </td>
+                  <td className="px-4 py-3">
+                    <div className="flex justify-end gap-2">
+                      <button
+                        onClick={() => onOpenTransaction(item.material_id, 'purchase')}
+                        className="inline-flex items-center gap-1 rounded-lg border border-emerald-300 px-2.5 py-1.5 text-xs text-emerald-700 transition hover:bg-emerald-50"
+                      >
+                        <Download className="h-3.5 w-3.5" />
+                        入庫
+                      </button>
+                      <button
+                        onClick={() => onOpenTransaction(item.material_id, 'use')}
+                        className="inline-flex items-center gap-1 rounded-lg border border-amber-300 px-2.5 py-1.5 text-xs text-amber-700 transition hover:bg-amber-50"
+                      >
+                        <Upload className="h-3.5 w-3.5" />
+                        出庫
+                      </button>
+                      <button
+                        onClick={() => onToggleHistory(item.material_id)}
+                        className="inline-flex items-center gap-1 rounded-lg border border-gray-300 px-2.5 py-1.5 text-xs text-gray-700 transition hover:bg-gray-100"
+                      >
+                        <Clock3 className="h-3.5 w-3.5" />
+                        履歴
+                      </button>
+                    </div>
+                  </td>
+                </tr>
+                {isExpanded && (
+                  <tr className="bg-gray-50/70">
+                    <td colSpan={7} className="px-4 py-4">
+                      <div className="rounded-xl border border-gray-200 bg-white p-4">
+                        <div className="mb-3 flex items-center justify-between">
+                          <h3 className="text-sm font-semibold text-gray-800">
+                            {item.name} の入出庫履歴
+                          </h3>
+                          {historyLoadingId === item.material_id && (
+                            <span className="text-xs text-gray-500">読み込み中...</span>
+                          )}
+                        </div>
+                        {history.length === 0 ? (
+                          <p className="text-sm text-gray-500">履歴はまだありません。</p>
+                        ) : (
+                          <div className="space-y-2">
+                            {history.map((transaction) => (
+                              <div
+                                key={transaction.id}
+                                className="flex flex-col gap-1 rounded-lg border border-gray-200 px-3 py-2 text-sm text-gray-700 sm:flex-row sm:items-center sm:justify-between"
+                              >
+                                <div className="flex items-center gap-3">
+                                  <span className="font-medium text-gray-900">
+                                    {transaction.transaction_type_display}
+                                  </span>
+                                  <span>
+                                    {transaction.quantity} {transaction.stock_unit_display}
+                                  </span>
+                                  <span className="text-gray-500">{transaction.occurred_on}</span>
+                                </div>
+                                <span className="text-gray-500">
+                                  {transaction.note || '備考なし'}
+                                </span>
+                              </div>
+                            ))}
+                          </div>
+                        )}
+                      </div>
+                    </td>
+                  </tr>
+                )}
+              </Fragment>
+            );
+          })}
+        </tbody>
+      </table>
+    </div>
+  );
+}
--- a/frontend/src/app/materials/_components/StockTransactionForm.tsx
+++ b/frontend/src/app/materials/_components/StockTransactionForm.tsx
@@ -0,0 +1,211 @@
+'use client';
+
+import { useEffect, useState } from 'react';
+import { Loader2, X } from 'lucide-react';
+
+import { api } from '@/lib/api';
+import { Material, StockTransaction } from '@/types';
+
+type TransactionType = StockTransaction['transaction_type'];
+
+interface StockTransactionFormProps {
+  isOpen: boolean;
+  materials: Material[];
+  presetMaterialId?: number | null;
+  presetTransactionType?: TransactionType | null;
+  onClose: () => void;
+  onSaved: () => Promise<void> | void;
+}
+
+const transactionOptions: { value: TransactionType; label: string }[] = [
+  { value: 'purchase', label: '入庫' },
+  { value: 'use', label: '使用' },
+  { value: 'adjustment_plus', label: '棚卸増' },
+  { value: 'adjustment_minus', label: '棚卸減' },
+  { value: 'discard', label: '廃棄' },
+];
+
+const today = () => new Date().toISOString().slice(0, 10);
+
+export default function StockTransactionForm({
+  isOpen,
+  materials,
+  presetMaterialId = null,
+  presetTransactionType = null,
+  onClose,
+  onSaved,
+}: StockTransactionFormProps) {
+  const [materialId, setMaterialId] = useState<string>('');
+  const [transactionType, setTransactionType] = useState<TransactionType>('purchase');
+  const [quantity, setQuantity] = useState('');
+  const [occurredOn, setOccurredOn] = useState(today());
+  const [note, setNote] = useState('');
+  const [saving, setSaving] = useState(false);
+  const [error, setError] = useState<string | null>(null);
+
+  useEffect(() => {
+    if (!isOpen) {
+      return;
+    }
+    setMaterialId(presetMaterialId ? String(presetMaterialId) : '');
+    setTransactionType(presetTransactionType ?? 'purchase');
+    setQuantity('');
+    setOccurredOn(today());
+    setNote('');
+    setError(null);
+  }, [isOpen, presetMaterialId, presetTransactionType]);
+
+  if (!isOpen) {
+    return null;
+  }
+
+  const handleSave = async () => {
+    setError(null);
+
+    if (!materialId) {
+      setError('資材を選択してください。');
+      return;
+    }
+    if (!quantity || Number(quantity) <= 0) {
+      setError('数量は0より大きい値を入力してください。');
+      return;
+    }
+
+    setSaving(true);
+    try {
+      await api.post('/materials/stock-transactions/', {
+        material: Number(materialId),
+        transaction_type: transactionType,
+        quantity,
+        occurred_on: occurredOn,
+        note,
+      });
+      await onSaved();
+      onClose();
+    } catch (e: unknown) {
+      const detail =
+        typeof e === 'object' &&
+        e !== null &&
+        'response' in e &&
+        typeof e.response === 'object' &&
+        e.response !== null &&
+        'data' in e.response
+          ? JSON.stringify(e.response.data)
+          : '入出庫の登録に失敗しました。';
+      setError(detail);
+    } finally {
+      setSaving(false);
+    }
+  };
+
+  return (
+    <div className="fixed inset-0 z-50 flex items-center justify-center bg-gray-900/40 px-4">
+      <div className="w-full max-w-lg rounded-2xl bg-white shadow-2xl">
+        <div className="flex items-center justify-between border-b border-gray-200 px-6 py-4">
+          <div>
+            <h2 className="text-lg font-semibold text-gray-900">入出庫登録</h2>
+            <p className="text-sm text-gray-500">在庫の増減を記録します。</p>
+          </div>
+          <button
+            onClick={onClose}
+            className="rounded-full p-2 text-gray-400 transition hover:bg-gray-100 hover:text-gray-600"
+          >
+            <X className="h-5 w-5" />
+          </button>
+        </div>
+
+        <div className="space-y-4 px-6 py-5">
+          {error && (
+            <div className="rounded-lg border border-red-300 bg-red-50 px-4 py-3 text-sm text-red-700">
+              {error}
+            </div>
+          )}
+
+          <label className="block">
+            <span className="mb-1 block text-sm font-medium text-gray-700">資材</span>
+            <select
+              value={materialId}
+              onChange={(e) => setMaterialId(e.target.value)}
+              className="w-full rounded-lg border border-gray-300 px-3 py-2 text-sm focus:border-green-500 focus:outline-none focus:ring-2 focus:ring-green-200"
+            >
+              <option value="">選択してください</option>
+              {materials.map((material) => (
+                <option key={material.id} value={material.id}>
+                  {material.name} ({material.material_type_display})
+                </option>
+              ))}
+            </select>
+          </label>
+
+          <div className="grid gap-4 sm:grid-cols-2">
+            <label className="block">
+              <span className="mb-1 block text-sm font-medium text-gray-700">取引種別</span>
+              <select
+                value={transactionType}
+                onChange={(e) => setTransactionType(e.target.value as TransactionType)}
+                className="w-full rounded-lg border border-gray-300 px-3 py-2 text-sm focus:border-green-500 focus:outline-none focus:ring-2 focus:ring-green-200"
+              >
+                {transactionOptions.map((option) => (
+                  <option key={option.value} value={option.value}>
+                    {option.label}
+                  </option>
+                ))}
+              </select>
+            </label>
+
+            <label className="block">
+              <span className="mb-1 block text-sm font-medium text-gray-700">数量</span>
+              <input
+                type="number"
+                min="0"
+                step="0.001"
+                value={quantity}
+                onChange={(e) => setQuantity(e.target.value)}
+                className="w-full rounded-lg border border-gray-300 px-3 py-2 text-sm focus:border-green-500 focus:outline-none focus:ring-2 focus:ring-green-200"
+                placeholder="0.000"
+              />
+            </label>
+          </div>
+
+          <label className="block">
+            <span className="mb-1 block text-sm font-medium text-gray-700">発生日</span>
+            <input
+              type="date"
+              value={occurredOn}
+              onChange={(e) => setOccurredOn(e.target.value)}
+              className="w-full rounded-lg border border-gray-300 px-3 py-2 text-sm focus:border-green-500 focus:outline-none focus:ring-2 focus:ring-green-200"
+            />
+          </label>
+
+          <label className="block">
+            <span className="mb-1 block text-sm font-medium text-gray-700">備考</span>
+            <textarea
+              value={note}
+              onChange={(e) => setNote(e.target.value)}
+              rows={3}
+              className="w-full rounded-lg border border-gray-300 px-3 py-2 text-sm focus:border-green-500 focus:outline-none focus:ring-2 focus:ring-green-200"
+              placeholder="任意でメモを残せます"
+            />
+          </label>
+        </div>
+
+        <div className="flex justify-end gap-3 border-t border-gray-200 px-6 py-4">
+          <button
+            onClick={onClose}
+            className="rounded-lg border border-gray-300 px-4 py-2 text-sm text-gray-700 transition hover:bg-gray-100"
+          >
+            キャンセル
+          </button>
+          <button
+            onClick={handleSave}
+            disabled={saving}
+            className="inline-flex items-center gap-2 rounded-lg bg-green-600 px-4 py-2 text-sm font-medium text-white transition hover:bg-green-700 disabled:cursor-not-allowed disabled:opacity-60"
+          >
+            {saving && <Loader2 className="h-4 w-4 animate-spin" />}
+            保存
+          </button>
+        </div>
+      </div>
+    </div>
+  );
+}
--- a/frontend/src/app/materials/masters/page.tsx
+++ b/frontend/src/app/materials/masters/page.tsx
@@ -0,0 +1,590 @@
+'use client';
+
+import { useEffect, useState } from 'react';
+import { ChevronLeft, Pencil, Plus, Trash2 } from 'lucide-react';
+import { useRouter } from 'next/navigation';
+
+import MaterialForm, {
+  MaterialFormState,
+  MaterialTab,
+} from '../_components/MaterialForm';
+import Navbar from '@/components/Navbar';
+import { api } from '@/lib/api';
+import { Material } from '@/types';
+
+const tabs: { key: MaterialTab; label: string }[] = [
+  { key: 'fertilizer', label: '肥料' },
+  { key: 'pesticide', label: '農薬' },
+  { key: 'misc', label: 'その他' },
+];
+
+const emptyForm = (tab: MaterialTab): MaterialFormState => ({
+  name: '',
+  material_type:
+    tab === 'fertilizer' ? 'fertilizer' : tab === 'pesticide' ? 'pesticide' : 'other',
+  maker: '',
+  stock_unit: tab === 'fertilizer' ? 'bag' : tab === 'pesticide' ? 'bottle' : 'piece',
+  is_active: true,
+  notes: '',
+  fertilizer_profile: {
+    capacity_kg: '',
+    nitrogen_pct: '',
+    phosphorus_pct: '',
+    potassium_pct: '',
+  },
+  pesticide_profile: {
+    registration_no: '',
+    formulation: '',
+    usage_unit: '',
+    dilution_ratio: '',
+    active_ingredient: '',
+    category: '',
+  },
+});
+
+export default function MaterialMastersPage() {
+  const router = useRouter();
+  const [tab, setTab] = useState<MaterialTab>('fertilizer');
+  const [materials, setMaterials] = useState<Material[]>([]);
+  const [loading, setLoading] = useState(true);
+  const [editingId, setEditingId] = useState<number | 'new' | null>(null);
+  const [form, setForm] = useState<MaterialFormState>(emptyForm('fertilizer'));
+  const [saving, setSaving] = useState(false);
+  const [error, setError] = useState<string | null>(null);
+
+  useEffect(() => {
+    fetchMaterials();
+  }, []);
+
+  useEffect(() => {
+    if (editingId === 'new') {
+      setForm(emptyForm(tab));
+    }
+  }, [tab, editingId]);
+
+  const fetchMaterials = async () => {
+    setLoading(true);
+    try {
+      const res = await api.get('/materials/materials/');
+      setMaterials(res.data);
+    } catch (e) {
+      console.error(e);
+      setError('資材マスタの取得に失敗しました。');
+    } finally {
+      setLoading(false);
+    }
+  };
+
+  const visibleMaterials = materials.filter((material) => {
+    if (tab === 'misc') {
+      return material.material_type === 'other' || material.material_type === 'seedling';
+    }
+    return material.material_type === tab;
+  });
+
+  const startNew = () => {
+    setError(null);
+    setForm(emptyForm(tab));
+    setEditingId('new');
+  };
+
+  const startEdit = (material: Material) => {
+    setError(null);
+    setForm({
+      name: material.name,
+      material_type: material.material_type,
+      maker: material.maker,
+      stock_unit: material.stock_unit,
+      is_active: material.is_active,
+      notes: material.notes,
+      fertilizer_profile: {
+        capacity_kg: material.fertilizer_profile?.capacity_kg ?? '',
+        nitrogen_pct: material.fertilizer_profile?.nitrogen_pct ?? '',
+        phosphorus_pct: material.fertilizer_profile?.phosphorus_pct ?? '',
+        potassium_pct: material.fertilizer_profile?.potassium_pct ?? '',
+      },
+      pesticide_profile: {
+        registration_no: material.pesticide_profile?.registration_no ?? '',
+        formulation: material.pesticide_profile?.formulation ?? '',
+        usage_unit: material.pesticide_profile?.usage_unit ?? '',
+        dilution_ratio: material.pesticide_profile?.dilution_ratio ?? '',
+        active_ingredient: material.pesticide_profile?.active_ingredient ?? '',
+        category: material.pesticide_profile?.category ?? '',
+      },
+    });
+    setEditingId(material.id);
+  };
+
+  const cancelEdit = () => {
+    setEditingId(null);
+    setForm(emptyForm(tab));
+  };
+
+  const handleSave = async () => {
+    setError(null);
+
+    if (!form.name.trim()) {
+      setError('資材名を入力してください。');
+      return;
+    }
+
+    setSaving(true);
+    try {
+      const payload = {
+        name: form.name,
+        material_type: form.material_type,
+        maker: form.maker,
+        stock_unit: form.stock_unit,
+        is_active: form.is_active,
+        notes: form.notes,
+        fertilizer_profile:
+          form.material_type === 'fertilizer'
+            ? {
+                capacity_kg: form.fertilizer_profile.capacity_kg || null,
+                nitrogen_pct: form.fertilizer_profile.nitrogen_pct || null,
+                phosphorus_pct: form.fertilizer_profile.phosphorus_pct || null,
+                potassium_pct: form.fertilizer_profile.potassium_pct || null,
+              }
+            : undefined,
+        pesticide_profile:
+          form.material_type === 'pesticide'
+            ? {
+                registration_no: form.pesticide_profile.registration_no,
+                formulation: form.pesticide_profile.formulation,
+                usage_unit: form.pesticide_profile.usage_unit,
+                dilution_ratio: form.pesticide_profile.dilution_ratio,
+                active_ingredient: form.pesticide_profile.active_ingredient,
+                category: form.pesticide_profile.category,
+              }
+            : undefined,
+      };
+
+      if (editingId === 'new') {
+        await api.post('/materials/materials/', payload);
+      } else {
+        await api.put(`/materials/materials/${editingId}/`, payload);
+      }
+
+      await fetchMaterials();
+      setEditingId(null);
+      setForm(emptyForm(tab));
+    } catch (e: unknown) {
+      console.error(e);
+      const detail =
+        typeof e === 'object' &&
+        e !== null &&
+        'response' in e &&
+        typeof e.response === 'object' &&
+        e.response !== null &&
+        'data' in e.response
+          ? JSON.stringify(e.response.data)
+          : '保存に失敗しました。';
+      setError(detail);
+    } finally {
+      setSaving(false);
+    }
+  };
+
+  const handleDelete = async (material: Material) => {
+    setError(null);
+    try {
+      await api.delete(`/materials/materials/${material.id}/`);
+      await fetchMaterials();
+    } catch (e: unknown) {
+      console.error(e);
+      const detail =
+        typeof e === 'object' &&
+        e !== null &&
+        'response' in e &&
+        typeof e.response === 'object' &&
+        e.response !== null &&
+        'data' in e.response
+          ? JSON.stringify(e.response.data)
+          : `「${material.name}」の削除に失敗しました。`;
+      setError(detail);
+    }
+  };
+
+  const handleBaseFieldChange = (
+    field: keyof Omit<MaterialFormState, 'fertilizer_profile' | 'pesticide_profile'>,
+    value: string | boolean
+  ) => {
+    setForm((prev) => ({
+      ...prev,
+      [field]: value,
+    }));
+  };
+
+  const handleFertilizerFieldChange = (
+    field: keyof MaterialFormState['fertilizer_profile'],
+    value: string
+  ) => {
+    setForm((prev) => ({
+      ...prev,
+      fertilizer_profile: {
+        ...prev.fertilizer_profile,
+        [field]: value,
+      },
+    }));
+  };
+
+  const handlePesticideFieldChange = (
+    field: keyof MaterialFormState['pesticide_profile'],
+    value: string
+  ) => {
+    setForm((prev) => ({
+      ...prev,
+      pesticide_profile: {
+        ...prev.pesticide_profile,
+        [field]: value,
+      },
+    }));
+  };
+
+  return (
+    <div className="min-h-screen bg-gray-50">
+      <Navbar />
+      <div className="mx-auto max-w-7xl px-4 py-8">
+        <div className="mb-6 flex items-center justify-between">
+          <div className="flex items-center gap-3">
+            <button
+              onClick={() => router.push('/materials')}
+              className="text-gray-500 transition hover:text-gray-700"
+            >
+              <ChevronLeft className="h-5 w-5" />
+            </button>
+            <div>
+              <h1 className="text-2xl font-bold text-gray-800">資材マスタ管理</h1>
+              <p className="text-sm text-gray-500">資材情報をインラインで編集できます。</p>
+            </div>
+          </div>
+          <button
+            onClick={startNew}
+            disabled={editingId !== null}
+            className="inline-flex items-center gap-2 rounded-lg bg-green-600 px-4 py-2 text-sm font-medium text-white transition hover:bg-green-700 disabled:cursor-not-allowed disabled:opacity-50"
+          >
+            <Plus className="h-4 w-4" />
+            新規追加
+          </button>
+        </div>
+
+        <div className="mb-5 flex flex-wrap gap-2">
+          {tabs.map((item) => (
+            <button
+              key={item.key}
+              onClick={() => {
+                setTab(item.key);
+                setEditingId(null);
+                setForm(emptyForm(item.key));
+              }}
+              className={`rounded-full px-4 py-2 text-sm font-medium transition ${
+                tab === item.key
+                  ? 'bg-green-600 text-white shadow-sm'
+                  : 'bg-white text-gray-600 hover:bg-gray-100'
+              }`}
+            >
+              {item.label}
+            </button>
+          ))}
+        </div>
+
+        {error && (
+          <div className="mb-4 flex items-start gap-2 rounded-xl border border-red-300 bg-red-50 px-4 py-3 text-sm text-red-700">
+            <span>{error}</span>
+            <button
+              onClick={() => setError(null)}
+              className="ml-auto text-red-400 transition hover:text-red-600"
+            >
+              ×
+            </button>
+          </div>
+        )}
+
+        {loading ? (
+          <p className="text-sm text-gray-500">読み込み中...</p>
+        ) : (
+          <div className="overflow-x-auto rounded-2xl border border-gray-200 bg-white shadow-sm">
+            {tab === 'fertilizer' && (
+              <FertilizerTable
+                materials={visibleMaterials}
+                editingId={editingId}
+                form={form}
+                saving={saving}
+                onEdit={startEdit}
+                onDelete={handleDelete}
+                onBaseFieldChange={handleBaseFieldChange}
+                onFertilizerFieldChange={handleFertilizerFieldChange}
+                onPesticideFieldChange={handlePesticideFieldChange}
+                onSave={handleSave}
+                onCancel={cancelEdit}
+              />
+            )}
+            {tab === 'pesticide' && (
+              <PesticideTable
+                materials={visibleMaterials}
+                editingId={editingId}
+                form={form}
+                saving={saving}
+                onEdit={startEdit}
+                onDelete={handleDelete}
+                onBaseFieldChange={handleBaseFieldChange}
+                onFertilizerFieldChange={handleFertilizerFieldChange}
+                onPesticideFieldChange={handlePesticideFieldChange}
+                onSave={handleSave}
+                onCancel={cancelEdit}
+              />
+            )}
+            {tab === 'misc' && (
+              <MiscTable
+                materials={visibleMaterials}
+                editingId={editingId}
+                form={form}
+                saving={saving}
+                onEdit={startEdit}
+                onDelete={handleDelete}
+                onBaseFieldChange={handleBaseFieldChange}
+                onFertilizerFieldChange={handleFertilizerFieldChange}
+                onPesticideFieldChange={handlePesticideFieldChange}
+                onSave={handleSave}
+                onCancel={cancelEdit}
+              />
+            )}
+          </div>
+        )}
+      </div>
+    </div>
+  );
+}
+
+interface TableProps {
+  materials: Material[];
+  editingId: number | 'new' | null;
+  form: MaterialFormState;
+  saving: boolean;
+  onEdit: (material: Material) => void;
+  onDelete: (material: Material) => void;
+  onBaseFieldChange: (
+    field: keyof Omit<MaterialFormState, 'fertilizer_profile' | 'pesticide_profile'>,
+    value: string | boolean
+  ) => void;
+  onFertilizerFieldChange: (
+    field: keyof MaterialFormState['fertilizer_profile'],
+    value: string
+  ) => void;
+  onPesticideFieldChange: (
+    field: keyof MaterialFormState['pesticide_profile'],
+    value: string
+  ) => void;
+  onSave: () => void;
+  onCancel: () => void;
+}
+
+function FertilizerTable(props: TableProps) {
+  return (
+    <table className="min-w-full text-sm">
+      <thead className="bg-gray-50">
+        <tr className="border-b border-gray-200">
+          <th className="px-4 py-3 text-left font-medium text-gray-700">資材名</th>
+          <th className="px-4 py-3 text-left font-medium text-gray-700">メーカー</th>
+          <th className="px-4 py-3 text-right font-medium text-gray-700">1袋(kg)</th>
+          <th className="px-4 py-3 text-right font-medium text-gray-700">窒素(%)</th>
+          <th className="px-4 py-3 text-right font-medium text-gray-700">リン酸(%)</th>
+          <th className="px-4 py-3 text-right font-medium text-gray-700">カリ(%)</th>
+          <th className="px-4 py-3 text-left font-medium text-gray-700">単位</th>
+          <th className="px-4 py-3 text-left font-medium text-gray-700">備考</th>
+          <th className="px-4 py-3 text-center font-medium text-gray-700">使用中</th>
+          <th className="px-4 py-3 text-right font-medium text-gray-700">操作</th>
+        </tr>
+      </thead>
+      <tbody className="divide-y divide-gray-100">
+        {props.editingId === 'new' && <MaterialForm tab="fertilizer" {...props} />}
+        {props.materials.map((material) =>
+          props.editingId === material.id ? (
+            <MaterialForm key={material.id} tab="fertilizer" {...props} />
+          ) : (
+            <tr key={material.id} className="hover:bg-gray-50">
+              <td className="px-4 py-3 font-medium text-gray-900">{material.name}</td>
+              <td className="px-4 py-3 text-gray-600">{material.maker || '-'}</td>
+              <td className="px-4 py-3 text-right text-gray-600">
+                {material.fertilizer_profile?.capacity_kg ?? '-'}
+              </td>
+              <td className="px-4 py-3 text-right text-gray-600">
+                {material.fertilizer_profile?.nitrogen_pct ?? '-'}
+              </td>
+              <td className="px-4 py-3 text-right text-gray-600">
+                {material.fertilizer_profile?.phosphorus_pct ?? '-'}
+              </td>
+              <td className="px-4 py-3 text-right text-gray-600">
+                {material.fertilizer_profile?.potassium_pct ?? '-'}
+              </td>
+              <td className="px-4 py-3 text-gray-600">{material.stock_unit_display}</td>
+              <td className="max-w-xs px-4 py-3 text-gray-600">{material.notes || '-'}</td>
+              <td className="px-4 py-3 text-center text-gray-600">
+                {material.is_active ? '○' : '-'}
+              </td>
+              <td className="px-4 py-3">
+                <RowActions
+                  disabled={props.editingId !== null}
+                  onEdit={() => props.onEdit(material)}
+                  onDelete={() => props.onDelete(material)}
+                />
+              </td>
+            </tr>
+          )
+        )}
+        {props.materials.length === 0 && props.editingId === null && (
+          <tr>
+            <td colSpan={10} className="px-4 py-8 text-center text-gray-400">
+              該当する資材が登録されていません
+            </td>
+          </tr>
+        )}
+      </tbody>
+    </table>
+  );
+}
+
+function PesticideTable(props: TableProps) {
+  return (
+    <table className="min-w-full text-sm">
+      <thead className="bg-gray-50">
+        <tr className="border-b border-gray-200">
+          <th className="px-4 py-3 text-left font-medium text-gray-700">資材名</th>
+          <th className="px-4 py-3 text-left font-medium text-gray-700">メーカー</th>
+          <th className="px-4 py-3 text-left font-medium text-gray-700">登録番号</th>
+          <th className="px-4 py-3 text-left font-medium text-gray-700">剤型</th>
+          <th className="px-4 py-3 text-left font-medium text-gray-700">有効成分</th>
+          <th className="px-4 py-3 text-left font-medium text-gray-700">分類</th>
+          <th className="px-4 py-3 text-left font-medium text-gray-700">単位</th>
+          <th className="px-4 py-3 text-left font-medium text-gray-700">備考</th>
+          <th className="px-4 py-3 text-center font-medium text-gray-700">使用中</th>
+          <th className="px-4 py-3 text-right font-medium text-gray-700">操作</th>
+        </tr>
+      </thead>
+      <tbody className="divide-y divide-gray-100">
+        {props.editingId === 'new' && <MaterialForm tab="pesticide" {...props} />}
+        {props.materials.map((material) =>
+          props.editingId === material.id ? (
+            <MaterialForm key={material.id} tab="pesticide" {...props} />
+          ) : (
+            <tr key={material.id} className="hover:bg-gray-50">
+              <td className="px-4 py-3 font-medium text-gray-900">{material.name}</td>
+              <td className="px-4 py-3 text-gray-600">{material.maker || '-'}</td>
+              <td className="px-4 py-3 text-gray-600">
+                {material.pesticide_profile?.registration_no || '-'}
+              </td>
+              <td className="px-4 py-3 text-gray-600">
+                {material.pesticide_profile?.formulation || '-'}
+              </td>
+              <td className="px-4 py-3 text-gray-600">
+                {material.pesticide_profile?.active_ingredient || '-'}
+              </td>
+              <td className="px-4 py-3 text-gray-600">
+                {material.pesticide_profile?.category || '-'}
+              </td>
+              <td className="px-4 py-3 text-gray-600">{material.stock_unit_display}</td>
+              <td className="max-w-xs px-4 py-3 text-gray-600">{material.notes || '-'}</td>
+              <td className="px-4 py-3 text-center text-gray-600">
+                {material.is_active ? '○' : '-'}
+              </td>
+              <td className="px-4 py-3">
+                <RowActions
+                  disabled={props.editingId !== null}
+                  onEdit={() => props.onEdit(material)}
+                  onDelete={() => props.onDelete(material)}
+                />
+              </td>
+            </tr>
+          )
+        )}
+        {props.materials.length === 0 && props.editingId === null && (
+          <tr>
+            <td colSpan={10} className="px-4 py-8 text-center text-gray-400">
+              該当する資材が登録されていません
+            </td>
+          </tr>
+        )}
+      </tbody>
+    </table>
+  );
+}
+
+function MiscTable(props: TableProps) {
+  return (
+    <table className="min-w-full text-sm">
+      <thead className="bg-gray-50">
+        <tr className="border-b border-gray-200">
+          <th className="px-4 py-3 text-left font-medium text-gray-700">資材名</th>
+          <th className="px-4 py-3 text-left font-medium text-gray-700">種別</th>
+          <th className="px-4 py-3 text-left font-medium text-gray-700">メーカー</th>
+          <th className="px-4 py-3 text-left font-medium text-gray-700">単位</th>
+          <th className="px-4 py-3 text-left font-medium text-gray-700">備考</th>
+          <th className="px-4 py-3 text-center font-medium text-gray-700">使用中</th>
+          <th className="px-4 py-3 text-right font-medium text-gray-700">操作</th>
+        </tr>
+      </thead>
+      <tbody className="divide-y divide-gray-100">
+        {props.editingId === 'new' && <MaterialForm tab="misc" {...props} />}
+        {props.materials.map((material) =>
+          props.editingId === material.id ? (
+            <MaterialForm key={material.id} tab="misc" {...props} />
+          ) : (
+            <tr key={material.id} className="hover:bg-gray-50">
+              <td className="px-4 py-3 font-medium text-gray-900">{material.name}</td>
+              <td className="px-4 py-3 text-gray-600">{material.material_type_display}</td>
+              <td className="px-4 py-3 text-gray-600">{material.maker || '-'}</td>
+              <td className="px-4 py-3 text-gray-600">{material.stock_unit_display}</td>
+              <td className="max-w-xs px-4 py-3 text-gray-600">{material.notes || '-'}</td>
+              <td className="px-4 py-3 text-center text-gray-600">
+                {material.is_active ? '○' : '-'}
+              </td>
+              <td className="px-4 py-3">
+                <RowActions
+                  disabled={props.editingId !== null}
+                  onEdit={() => props.onEdit(material)}
+                  onDelete={() => props.onDelete(material)}
+                />
+              </td>
+            </tr>
+          )
+        )}
+        {props.materials.length === 0 && props.editingId === null && (
+          <tr>
+            <td colSpan={7} className="px-4 py-8 text-center text-gray-400">
+              該当する資材が登録されていません
+            </td>
+          </tr>
+        )}
+      </tbody>
+    </table>
+  );
+}
+
+function RowActions({
+  disabled,
+  onEdit,
+  onDelete,
+}: {
+  disabled: boolean;
+  onEdit: () => void;
+  onDelete: () => void;
+}) {
+  return (
+    <div className="flex items-center justify-end gap-2">
+      <button
+        onClick={onEdit}
+        disabled={disabled}
+        className="text-gray-400 transition hover:text-blue-600 disabled:opacity-30"
+      >
+        <Pencil className="h-4 w-4" />
+      </button>
+      <button
+        onClick={onDelete}
+        disabled={disabled}
+        className="text-gray-400 transition hover:text-red-600 disabled:opacity-30"
+      >
+        <Trash2 className="h-4 w-4" />
+      </button>
+    </div>
+  );
+}
--- a/frontend/src/app/materials/page.tsx
+++ b/frontend/src/app/materials/page.tsx
@@ -0,0 +1,208 @@
+'use client';
+
+import { useEffect, useState } from 'react';
+import { Package, Plus, Settings2 } from 'lucide-react';
+import { useRouter } from 'next/navigation';
+
+import StockOverview from './_components/StockOverview';
+import StockTransactionForm from './_components/StockTransactionForm';
+import Navbar from '@/components/Navbar';
+import { api } from '@/lib/api';
+import { Material, StockSummary, StockTransaction } from '@/types';
+
+type FilterTab = 'all' | 'fertilizer' | 'pesticide' | 'misc';
+
+const tabs: { key: FilterTab; label: string }[] = [
+  { key: 'all', label: '全て' },
+  { key: 'fertilizer', label: '肥料' },
+  { key: 'pesticide', label: '農薬' },
+  { key: 'misc', label: 'その他' },
+];
+
+export default function MaterialsPage() {
+  const router = useRouter();
+  const [tab, setTab] = useState<FilterTab>('all');
+  const [loading, setLoading] = useState(true);
+  const [materials, setMaterials] = useState<Material[]>([]);
+  const [summaries, setSummaries] = useState<StockSummary[]>([]);
+  const [histories, setHistories] = useState<Record<number, StockTransaction[]>>({});
+  const [expandedMaterialId, setExpandedMaterialId] = useState<number | null>(null);
+  const [historyLoadingId, setHistoryLoadingId] = useState<number | null>(null);
+  const [error, setError] = useState<string | null>(null);
+  const [isTransactionOpen, setIsTransactionOpen] = useState(false);
+  const [presetMaterialId, setPresetMaterialId] = useState<number | null>(null);
+  const [presetTransactionType, setPresetTransactionType] =
+    useState<StockTransaction['transaction_type'] | null>(null);
+
+  useEffect(() => {
+    fetchInitialData();
+  }, []);
+
+  const fetchInitialData = async () => {
+    setLoading(true);
+    setError(null);
+    try {
+      const [materialsRes, summariesRes] = await Promise.all([
+        api.get('/materials/materials/'),
+        api.get('/materials/stock-summary/'),
+      ]);
+      setMaterials(materialsRes.data);
+      setSummaries(summariesRes.data);
+    } catch (e) {
+      console.error(e);
+      setError('在庫データの取得に失敗しました。');
+    } finally {
+      setLoading(false);
+    }
+  };
+
+  const fetchSummaryOnly = async () => {
+    try {
+      const res = await api.get('/materials/stock-summary/');
+      setSummaries(res.data);
+    } catch (e) {
+      console.error(e);
+      setError('在庫一覧の更新に失敗しました。');
+    }
+  };
+
+  const handleToggleHistory = async (materialId: number) => {
+    if (expandedMaterialId === materialId) {
+      setExpandedMaterialId(null);
+      return;
+    }
+
+    setExpandedMaterialId(materialId);
+    if (histories[materialId]) {
+      return;
+    }
+
+    setHistoryLoadingId(materialId);
+    try {
+      const res = await api.get(`/materials/stock-transactions/?material_id=${materialId}`);
+      setHistories((prev) => ({ ...prev, [materialId]: res.data }));
+    } catch (e) {
+      console.error(e);
+      setError('履歴の取得に失敗しました。');
+    } finally {
+      setHistoryLoadingId(null);
+    }
+  };
+
+  const handleOpenTransaction = (
+    materialId: number | null,
+    transactionType: StockTransaction['transaction_type'] | null
+  ) => {
+    setPresetMaterialId(materialId);
+    setPresetTransactionType(transactionType);
+    setIsTransactionOpen(true);
+  };
+
+  const handleSavedTransaction = async () => {
+    await fetchSummaryOnly();
+
+    if (expandedMaterialId !== null) {
+      try {
+        const res = await api.get(
+          `/materials/stock-transactions/?material_id=${expandedMaterialId}`
+        );
+        setHistories((prev) => ({ ...prev, [expandedMaterialId]: res.data }));
+      } catch (e) {
+        console.error(e);
+      }
+    }
+  };
+
+  const filteredSummaries = summaries.filter((summary) => {
+    if (tab === 'all') {
+      return true;
+    }
+    if (tab === 'misc') {
+      return summary.material_type === 'other' || summary.material_type === 'seedling';
+    }
+    return summary.material_type === tab;
+  });
+
+  return (
+    <div className="min-h-screen bg-gray-50">
+      <Navbar />
+      <div className="mx-auto max-w-6xl px-4 py-8">
+        <div className="mb-6 flex flex-col gap-4 rounded-3xl bg-gradient-to-r from-emerald-600 via-green-600 to-lime-500 px-6 py-7 text-white shadow-lg sm:flex-row sm:items-end sm:justify-between">
+          <div>
+            <div className="mb-3 inline-flex items-center gap-2 rounded-full bg-white/15 px-3 py-1 text-sm">
+              <Package className="h-4 w-4" />
+              Materials Inventory
+            </div>
+            <h1 className="text-2xl font-semibold">在庫管理</h1>
+            <p className="mt-2 text-sm text-emerald-50">
+              資材ごとの現在庫と入出庫履歴をまとめて確認できます。
+            </p>
+          </div>
+          <div className="flex flex-wrap gap-3">
+            <button
+              onClick={() => router.push('/materials/masters')}
+              className="inline-flex items-center gap-2 rounded-xl border border-white/30 bg-white/10 px-4 py-2 text-sm font-medium text-white transition hover:bg-white/20"
+            >
+              <Settings2 className="h-4 w-4" />
+              資材マスタ
+            </button>
+            <button
+              onClick={() => handleOpenTransaction(null, null)}
+              className="inline-flex items-center gap-2 rounded-xl bg-white px-4 py-2 text-sm font-medium text-green-700 transition hover:bg-green-50"
+            >
+              <Plus className="h-4 w-4" />
+              入出庫登録
+            </button>
+          </div>
+        </div>
+
+        {error && (
+          <div className="mb-4 flex items-start gap-2 rounded-xl border border-red-300 bg-red-50 px-4 py-3 text-sm text-red-700">
+            <span>{error}</span>
+            <button
+              onClick={() => setError(null)}
+              className="ml-auto text-red-400 transition hover:text-red-600"
+            >
+              ×
+            </button>
+          </div>
+        )}
+
+        <div className="mb-5 flex flex-wrap gap-2">
+          {tabs.map((item) => (
+            <button
+              key={item.key}
+              onClick={() => setTab(item.key)}
+              className={`rounded-full px-4 py-2 text-sm font-medium transition ${
+                tab === item.key
+                  ? 'bg-green-600 text-white shadow-sm'
+                  : 'bg-white text-gray-600 hover:bg-gray-100'
+              }`}
+            >
+              {item.label}
+            </button>
+          ))}
+        </div>
+
+        <StockOverview
+          loading={loading}
+          items={filteredSummaries}
+          expandedMaterialId={expandedMaterialId}
+          historyLoadingId={historyLoadingId}
+          histories={histories}
+          onOpenTransaction={handleOpenTransaction}
+          onToggleHistory={handleToggleHistory}
+        />
+      </div>
+
+      <StockTransactionForm
+        isOpen={isTransactionOpen}
+        materials={materials}
+        presetMaterialId={presetMaterialId}
+        presetTransactionType={presetTransactionType}
+        onClose={() => setIsTransactionOpen(false)}
+        onSaved={handleSavedTransaction}
+      />
+    </div>
+  );
+}
--- a/frontend/src/components/Navbar.tsx
+++ b/frontend/src/components/Navbar.tsx
@@ -1,7 +1,7 @@
 'use client';

 import { useRouter, usePathname } from 'next/navigation';
-import { LogOut, Wheat, MapPin, FileText, Upload, LayoutDashboard, Mail, History, Shield, KeyRound, Cloud, Sprout, FlaskConical } from 'lucide-react';
+import { LogOut, Wheat, MapPin, FileText, Upload, LayoutDashboard, Mail, History, Shield, KeyRound, Cloud, Sprout, FlaskConical, Package } from 'lucide-react';
 import { logout } from '@/lib/api';

 export default function Navbar() {
@@ -133,6 +133,17 @@ export default function Navbar() {
                <FlaskConical className="h-4 w-4 mr-2" />
                分配計画
              </button>
+              <button
+                onClick={() => router.push('/materials')}
+                className={`flex items-center px-3 py-2 text-sm rounded-md transition-colors ${
+                  pathname?.startsWith('/materials')
+                    ? 'text-green-700 bg-green-50'
+                    : 'text-gray-700 hover:text-gray-900 hover:bg-gray-100'
+                }`}
+              >
+                <Package className="h-4 w-4 mr-2" />
+                在庫管理
+              </button>
            </div>
          </div>
          <div className="flex items-center space-x-1">
--- a/frontend/src/types/index.ts
+++ b/frontend/src/types/index.ts
@@ -65,6 +65,72 @@ export interface Fertilizer {
  phosphorus_pct: string | null;
  potassium_pct: string | null;
  notes: string | null;
+  material: number | null;
+  material_id: number | null;
+}
+
+export interface FertilizerProfile {
+  capacity_kg: string | null;
+  nitrogen_pct: string | null;
+  phosphorus_pct: string | null;
+  potassium_pct: string | null;
+}
+
+export interface PesticideProfile {
+  registration_no: string;
+  formulation: string;
+  usage_unit: string;
+  dilution_ratio: string;
+  active_ingredient: string;
+  category: string;
+}
+
+export interface Material {
+  id: number;
+  name: string;
+  material_type: 'fertilizer' | 'pesticide' | 'seedling' | 'other';
+  material_type_display: string;
+  maker: string;
+  stock_unit: 'bag' | 'bottle' | 'kg' | 'liter' | 'piece';
+  stock_unit_display: string;
+  is_active: boolean;
+  notes: string;
+  fertilizer_profile: FertilizerProfile | null;
+  pesticide_profile: PesticideProfile | null;
+  current_stock: string;
+  created_at: string;
+  updated_at: string;
+}
+
+export interface StockTransaction {
+  id: number;
+  material: number;
+  material_name: string;
+  material_type: string;
+  transaction_type: 'purchase' | 'use' | 'reserve' | 'adjustment_plus' | 'adjustment_minus' | 'discard';
+  transaction_type_display: string;
+  quantity: string;
+  stock_unit: string;
+  stock_unit_display: string;
+  occurred_on: string;
+  note: string;
+  fertilization_plan: number | null;
+  created_at: string;
+}
+
+export interface StockSummary {
+  material_id: number;
+  name: string;
+  material_type: 'fertilizer' | 'pesticide' | 'seedling' | 'other';
+  material_type_display: string;
+  maker: string;
+  stock_unit: string;
+  stock_unit_display: string;
+  is_active: boolean;
+  current_stock: string;
+  reserved_stock: string;
+  available_stock: string;
+  last_transaction_date: string | null;
 }

 export interface FertilizationEntry {
@@ -88,6 +154,8 @@ export interface FertilizationPlan {
  entries: FertilizationEntry[];
  field_count: number;
  fertilizer_count: number;
+  is_confirmed: boolean;
+  confirmed_at: string | null;
  created_at: string;
  updated_at: string;
 }
--- a/frontend/tsconfig.tsbuildinfo
+++ b/frontend/tsconfig.tsbuildinfo
--- a/改善案/在庫管理機能実装案.md
+++ b/改善案/在庫管理機能実装案.md
Author	SHA1	Message	Date
Akira	e3c21d6e81	ConfirmSpreadingModal の改善点: groupedEntries（肥料別リスト表示）→ layout（圃場×肥料のマトリクス表）に変更 ✅ 施肥計画編集画面と同じ「圃場名 / 面積(反) / 肥料列... / 合計」のテーブル構造に統一 ✅ 各セルに計画値ラベル + 実績入力欄を縦並び ✅ 列合計（肥料別）・行合計（圃場別）・総合計を追加 ✅ 計画情報サマリーカード（年度・品種・圃場数・肥料数）を追加 ✅ 操作ガイド（sky色バナー）を追加 ✅ モーダル幅を max-w-4xl → max-w-[95vw] に拡大（マトリクス表に合わせて） ✅ ドキュメント更新: document/13_マスタードキュメント_施肥計画編.md — 在庫引当・散布確定・確定取消 API を追記 ✅ 改善案/在庫管理機能実装案.md — 微修正 ✅	2026-03-15 13:48:48 +09:00
Akira	72b4d670fe	完璧に動作しています。テスト結果確定取消 API ✅ is_confirmed: false, confirmed_at: null USE トランザクション削除 ✅ current_stock が 27.5→32 に復帰引当再作成 ✅ reserved_stock = 5.000 に復帰追加した変更: stock_service.py:81-93 — unconfirm_spreading(): USE削除→確定フラグリセット→引当再作成 fertilizer/views.py — unconfirm アクション（POST /api/fertilizer/plans/{id}/unconfirm/） fertilizer/page.tsx — 一覧に「確定取消」ボタン（確定済み計画のみ表示） FertilizerEditPage.tsx — 編集画面ヘッダーに「確定取消」ボタン + 在庫情報再取得	2026-03-15 13:28:02 +09:00
Akira	42b11a5df8	在庫管理 Phase 1.5（引当・散布確定）の設計を追記し、CODEX指示書を更新 - 在庫管理機能実装案.md: セクション23（引当・散布確定ワークフロー）を追加 - CODEX.md: Phase 1完了を受け、Phase 1.5実装指示に全面書き換え Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>	2026-03-14 17:29:05 +09:00
Akira	497bc87c24	在庫管理機能 Phase 1 実装（apps/materials + フロントエンド） Backend: - apps/materials 新規作成（Material, FertilizerProfile, PesticideProfile, StockTransaction） - 資材マスタ CRUD API（/api/materials/materials/） - 入出庫履歴 API（/api/materials/stock-transactions/） - 在庫集計 API（/api/materials/stock-summary/） - 既存 Fertilizer に material OneToOneField 追加（0005マイグレーション、データ移行込み） Frontend: - /materials: 在庫一覧画面（タブフィルタ、履歴展開、入出庫モーダル） - /materials/masters: 資材マスタ管理（肥料/農薬/その他タブ、インライン編集） - Navbar に「在庫管理」メニュー追加 - Material/StockTransaction/StockSummary 型定義追加 Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>	2026-03-14 15:42:47 +09:00
Akira	67d4197b7f	在庫管理機能実装案をレビュー反映し、CODEX実装指示書を追加 - StockTransaction から冗長フィールド除外（unit, reference_type/id, created_by, inventory_count） - フロントエンド画面構成を変更（入出庫登録をモーダル化、マスタ管理をタブ統合） - レビュー記録セクション22を追加 - CODEX.md: Phase 1 実装指示書を作成（モデル・API・画面の詳細仕様） Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>	2026-03-14 15:03:09 +09:00
Akira	1b619c44a0	在庫管理機能実装案.md に ## 21. 補足: 外部サブスクLLM活用案を追記しました。内容は、恵菜システム自身は LLM API を呼ばず、調査用プロンプトを提供する調査手順を表示する LLM回答を貼り付けてフォームへ反映するという実装案です。肥料用・農薬用のプロンプト例、画面イメージ、貼り付け結果の取り込み方式、メリットと注意点まで入れています。今回は文書更新のみで、コード変更やテストはしていません。必要なら次に、この貼り付け結果をフォームへ反映するための入力フォーマット仕様や、画面ワイヤー案まで具体化できます。	2026-03-13 18:29:03 +09:00
Akira	f1512febde	在庫管理機能実装案.md に、電気炉さいミネラルホウ素リン酸グアノも追記しました。追加した内容は、各資材についての袋表示・保証票ベースの情報、実装上の扱い、alias の例です。あわせて最後のまとめも更新して、5件を次の3パターンに整理しました。現場名と保証票名が違う: 仁井田米有機, 土佐勤農党, 電気炉さい現場名と表示名がほぼ一致する: リン酸グアノ公式マスタよりローカル資材管理向き: ミネラルホウ素今回は文書更新のみで、コード変更やテストはしていません。必要なら次に、この5件を前提にした MaterialAlias の Django モデル案まで具体化します。	2026-03-13 13:50:24 +09:00
Akira	776a269d6d	在庫管理機能実装案.md に ## 18. 補足: 肥料公式データ同期・あいまい検索案を追記しました。内容は、普通肥料を主対象に公式データをローカルDB化し、検索時はローカル検索、24時間超過時だけ裏で差分同期するという方針です。FertilizerOfficialMaster のテーブル案、既存 Fertilizer との紐づけ、検索API、同期ジョブ、特殊肥料は手入力併用にする考え方まで入れています。今回は文書更新のみで、コード変更やテスト実行はしていません。必要なら次は、この18章をもとに models.py レベルの実装草案まで起こせます。	2026-03-13 13:26:18 +09:00
Akira	1425094107	在庫管理機能実装案.md に、## 17. 補足: 農薬公式データ同期・あいまい検索案を追記しました。今回追加したのは、ローカルDBで即検索しつつ、24時間以上経過時だけ裏で差分同期する方式の具体化です。PesticideOfficialMaster と OfficialDataSyncStatus のテーブル案、検索API、同期ジョブ、差分更新ルール、フロントの再読込挙動、失敗時フォールバックまで入れてあります。文書更新のみで、コード変更やテスト実行はしていません。必要なら次に、この章をそのまま実装に落として、Django モデル案と API 仕様書を作れます。	2026-03-13 13:22:05 +09:00
Akira	f74dc4c4b7	在庫管理機能実装案	2026-03-13 13:13:40 +09:00