Symptoms: Brown spots or patches appear on the leaves. The affected areas are soft, dark brown, and often surrounded by a broad yellow halo. Disease Characteristics: This is a physiological disorder typically caused by overwatering, environmental pollution, or poor air circulation. If the spots are wrinkled and brown, it may indicate underwatering, which is the most common cause. If the leaves curl and drop off, excessive watering combined with low temperatures is likely the main factor. During the curing process, if the leaf loses its pattern and turns entirely green, this could be due to insufficient light or an overapplication of nitrogen fertilizer. Control Methods: Use well-rotted compost or peat-based potting mixes to ensure good drainage. Avoid overwatering—keep the soil consistently moist but not soggy. For storage and transport, use air-conditioned trucks or ensure proper ventilation 2–3 times daily. If the entire leaf turns green, move the plant to a well-lit area and add phosphorus and potassium fertilizers. If stems and leaves begin to rot, the condition can quickly worsen. At this point, improve curing conditions by reducing water intake. If necessary, apply a 27% copper hydroxide suspension or a 12% oxycopper emulsion diluted at 600 times. Always follow label instructions when using chemical treatments. It's important to monitor your plants regularly and adjust care practices based on their specific needs. Maintaining a balanced environment—adequate light, proper watering, and good airflow—can go a long way in preventing such issues. If you're unsure about the exact cause, consider consulting a local horticulturist or using a soil moisture meter to guide your watering schedule. ZHONGSHAN G.H.L. TRADING CO., LTD. , https://www.ghltrade.com