UPDATE

rag/services/fertilization.py

@@ -5,6 +5,7 @@
 import json
 import logging
 
+from farm_data.models import SensorData
 from rag.api_provider import get_chat_client
 from rag.chat import (
     _complete_audit_log,
@@ -78,13 +79,24 @@ def get_fertilization_recommendation(
 
     user_query = query or "توصیه کودهی برای مزرعه من چیست؟"
 
+    sensor = (
+        SensorData.objects.prefetch_related("plants")
+        .filter(farm_uuid=sensor_uuid)
+        .first()
+    )
+    resolved_plant_name = plant_name
+    if not resolved_plant_name and sensor is not None:
+        plant = sensor.plants.first()
+        if plant is not None:
+            resolved_plant_name = plant.name
+
     context = build_rag_context(
         user_query, sensor_uuid, config=cfg, limit=limit, kb_name=KB_NAME, service_id=SERVICE_ID,
     )
 
     extra_parts: list[str] = []
-    if plant_name and growth_stage:
-        plant_text = build_plant_text(plant_name, growth_stage)
+    if resolved_plant_name and growth_stage:
+        plant_text = build_plant_text(resolved_plant_name, growth_stage)
         if plant_text:
             extra_parts.append("[اطلاعات گیاه]\n" + plant_text)
     if extra_parts: