How to prevent and cure the gum disease of growing cherry

symptoms

Gummosis is an important disease of cherry. Its symptoms can be divided into two types: dry rot type and canker type. Dry rot type occurs mostly on the trunk and main branch. The initial disease spot is irregular, dark brown, hard surface, often causing glue flow. The later disease spot is long strip type, dry shrinkage depression, sometimes cracking around, and small black spots are densely produced on the surface. Canker type gummosis: resin is produced in the diseased part of the tree, but it does not flow out immediately, but remains between xylem and phloem. The diseased part is slightly raised and flows with sap, flowing out from the dermatome or wound of the diseased part. At first, the diseased part is colorless and slightly transparent or dark brown, hard.

causes

Dry rot type gummy disease consists of ascomycetes, tea? Conidiospores and ascospores spread by wind and rain, 4 to 10 months can be infected, mostly by wound invasion, with early disease. The fungus is a weak parasitic fungus, can only attack weak trees and weak branches, the weaker the tree, the more serious the disease.

Gum canker is caused by Botrytis vinifera belonging to Ascomycetes, which is a weak parasitic fungus with latent infection characteristics. After infected by the pathogen, resin is produced in the diseased part of the tree, but it does not flow out immediately, but remains between xylem and phloem. The diseased part slightly bulges and flows out from the bark hole or wound of the diseased part along with the sap flow. The diseased part is colorless and slightly transparent or dark brown at the beginning, and becomes dark brown and hard at the later stage. Wounds of branches damaged by insect pests, freezing injury, sunburn and other mechanical injuries are important entrances for bacteria to invade. Conidiospores are transmitted by rain. The sap flow disease began to flow from spring, and the disease gradually aggravated after early June, and the disease was most serious in rainy season.

prevention and control

1. In autumn and winter, add decomposed organic fertilizer to enhance tree vigor, improve disease resistance and avoid invasion of germs.

2. Collect dead branches and burn them or bury them deeply to prevent and control borers and pests, so as to reduce the source of disease and wounds.

3. Scrape and cure the disease spots. The disease spots are limited to the surface layer. After rain and snow weather in winter or spring, the glue flow is soft, so scrape it with sickle in time. At the same time, apply 50 times solution of 402 disease-resistant agent or 50 times solution of thiram arsenic to the wound, and then apply Bordeaux slurry for protection; or directly apply 5 degrees of stone sulfur mixture for prevention and control.

4. Before germination of seriously ill orchards, spray 40% thiram wettable powder 100 times solution. During growth, combine with prevention and control of other diseases, spray on branches for protection.