How to control walnut anthracnose with high temperature and heavy rain during the formation of walnut yield

The main formation period of walnut yield is from mid-late August to early September, which is due to high temperature and wet air and high incidence of various diseases, which seriously affects walnut production. During this period, walnut anthracnose was the main disease, and other diseases occurred slightly.

anthracnose of walnut

anthracnose of walnut

Disease symptoms: walnut after the damage, brown to dark brown on the pericarp long round or nearly round spots, the central depression, and there are small black spots, there are concentric ring-like. When the air humidity is high, there are raised pink spots on the spots. Spots when many, can be even into pieces, so that walnut black rot or early fall. Leaf spots, irregular shape, mostly strip. The leaf color of the diseased spot is yellow, and the seriously ill leaves are all yellow.

Condition of disease: from June to August, the disease occurred seriously in the kernel peach orchard with heavy rainfall, weak tree vigor, dense branches and leaves and extensive management, and the spores invaded from the wound or natural orifice of walnut fruit.

Control methods: (1) remove the diseased branches, focus on burning the diseased fruits and leaves. Strengthen tree management, ventilation and light transmission need to be improved. (2) When rainy season comes, spray Bordeaux mixture of 1:1:200(copper sulfate: lime: water) once every 10-15 days to prevent walnut anthracnose. (3) When the disease occurs, spray 40% Tuizheng WP 800 times solution, or 50% carbendazim WP 1000 times solution, 75% Chlorothalonil 600 times solution, 70% Thiophane 800 times solution, once every 15 days, continuously spray 2-3 times.