Control techniques of Leaf spot of Cymbidium

Symptoms: the disease mainly infects the leaves, and at the initial stage of the disease, the leaves have small brown spots, which gradually expand into large disease spots with irregular shape from yellowish brown to grayish brown. The part of the disease is slightly sunken and the edge is slightly raised. In the later stage, the disease spot is dry and there are small black spots on it.

Pathogen and pathogenesis: the pathogen is a kind of true bacteria. When too much nitrogen fertilizer and relatively less phosphorus and potassium fertilizer are applied in cultivation, the disease is easy to occur. Leaf spot disease is easy to occur under the condition of high temperature and drying, or when the insect is seriously damaged.

Prevention and control methods:

① was used to remove diseased leaves and remnants. Reduce the source of infection.

② can control shell insects, avoid insect pests and reduce infection.

In the early stage of ③, 50% carbendazim 1000-fold solution, 70% topiramine wettable powder 1000-fold solution, 50% Dysenamine 1000-fold solution were sprayed for prevention and treatment.