1. Symptom: This is a fungal disease. At the beginning of the disease, the leaves of the plant began to wilt, and the edge appeared yellow brown spot. Then the dry spot will gradually expand inward, and later the leaves will dry and fall off.
2. Prevention and control method: when the disease is found, the serious disease and the area within 2-3m around the disease can be irrigated in small area by using the green kuhlike, and the rest can be prevented by using the 500 fold solution.
1. Symptoms: at the beginning of the disease, small yellow spots will appear on the leaves, and then gradually expand into round or irregular spots. The lesions were yellow brown or gray brown, and a yellow halo appeared around the leaves.
2. Prevention and control method: remove the diseased leaves or plants in time and destroy them intensively. The disease can be treated with carbendazim spray.
1. Symptoms: root knot nematodes mainly damage the roots of plants. The symptom is that the number of fibrous roots and lateral roots increases, and white nodules of various shapes are formed on young roots. The above ground part of the diseased plant grows slowly and dies early when it is serious.
2. Prevention and control method: turn the soil deeply and change the soil for the plant, which can reduce the occurrence of insect pest. After birth, the diseased plant can be irrigated with 100 times of dibromochloropropane emulsifiable oil with 80% content.
