Scab harms pepper (sweet pepper). The disease mainly harms leaves, but also stems and fruits, and mostly occurs in the adult stage. Leaf diseases: At first, there were waterlogged, round and yellow-green spots on the back of leaves, and the front of the same diseased leaf faded, and then it expanded into irregular scab-like spots with dark brown to yellowish brown edges, slightly convex, light brown in the middle and slightly concave and rough epidermis. The diameter of the lesion varies from 0.5 to 65438 0.5 mm, and the blade and tip turn yellow, dry and fall off when it is seriously damaged. The stems and fruit stalks are diseased, which are dark green spots at first, then become irregular stripes or patches, yellow-brown, slightly convex, and longitudinally split into scab spots. Bacterial pus overflowed when it was wet.

Scab is a bacterial disease. The pathogen overwinters mainly on the surface of seeds, and can also overwinter in the soil with disease and residue. Seedlings get sick after sowing with bacteria; Overwintering bacteria in soil spread through wind and rain, invade from stomata or wounds, and carry out primary infection. The bacteria produced by reinfection spread through wind and rain, insects and agricultural operations. The growth temperature of the pathogen is 5 ~ 40℃, and the optimum temperature is 27 ~ 30℃. This disease is a high temperature disease. In July and August, high temperature and rainy weather, especially typhoon attacks and insect pests, promoted the epidemic of the disease. Continuous cropping, poor drainage, poor fertilizer growth plots are seriously ill.

Control measures (1) Agricultural control.

Rotation with non-solanaceae vegetables for 2 ~ 3 years, combined with deep tillage, to promote the decomposition of diseases and bacterial death; Collect seeds from disease-free plants.

(2) seed disinfection.

Seeds are soaked in warm water at 55℃ 10 minutes or warm water at 52℃ for 30 minutes, or soaked in green water 10 ~ 12 hours and then soaked in 0. 1% copper sulfate solution for 5 minutes.

(3) chemical control.

At the initial stage of the disease, 77% kocide wettable powder 500 times solution, 14% copper complex solution 300 times solution or neophytomycin 4000 times solution can be selected and sprayed once every 7 ~ 10 days for 2 ~ 3 times continuously.