What pesticide works well to control apple mosaic disease?

Apple mosaic disease occurs in most parts of the country and is a fairly common viral disease. On infected trees, the current-year shoots are shorter than those of healthy trees, the number of nodes is reduced, and the fruit does not store well. So, what pesticide should be used for apple mosaic disease?

1. What pesticide should be used for apple mosaic disease?

For apple mosaic disease, you can spray moroxydine hydrochloride and copper acetate, 1.5% zhibingling emulsion at 1000 times dilution, or chitosan at 500 times dilution alternately, spraying once every 10-15 days, for 2-3 consecutive sprays.

2. Types of apple mosaic disease

Apple mosaic disease is a leaf chlorosis symptom caused by a virus, and its field appearance is easily confused with yellow leaf disease caused by iron deficiency. Apple mosaic disease mainly shows on the leaves, forming various types of bright yellow or white lesions. Symptoms vary greatly depending on the severity of the disease, and there are roughly 5 types:

(1) Mottle type. This is the earliest and most common symptom type in mosaic disease. The lesions on the leaves are irregular in shape and vary in size, bright yellow, with clear edges; sometimes several lesions merge together into large patches.

(2) Mosaic type. The lesions are irregular, and large dark green or light green lesions appear on the diseased leaves, with unclear edges.

(3) Stripe type. The veins of the diseased leaves become chlorotic and yellow, and this extends to the nearby mesophyll tissue. Sometimes only the main vein and branch veins turn yellow, while the other parts remain green; sometimes the main vein, branch veins, and small veins all show relatively narrow yellowing, making the whole leaf appear net-veined. The diseased leaves appear relatively late.

(4) Ringspot type. Bright yellow ring-shaped or nearly ring-shaped markings appear on the leaves, and the inside of the ring markings remains green.

(5) Bordering type. The edges of the diseased leaves become yellow, forming a very narrow yellow border along the leaf edge, while the other parts of the diseased leaves are completely normal. Under natural conditions, various types of symptoms often occur mixed on the same diseased tree. Infected trees grow slowly, the diseased trees defoliate early, the fruit tastes bland, yield is reduced, and the fruit does not store well.

Apple mosaic disease causes relatively great harm to apples, and control is mainly preventive. This disease has strong seasonality and regionality. By understanding the occurrence of pests and diseases in different seasons and different regions, corresponding measures to control the harm of apple mosaic disease should be taken according to actual conditions, so as to ensure healthy plant growth.