Author: Zhongchuan Peony Publish Time: 2024-11-11 Origin: Site
Symptoms of Tree Peony Wheel Pattern Spot Disease:
At the onset of the disease, the lesions on the leaves are circular or nearly circular in shape, with a diameter of 4-10mm and a large quantity. They are light brown to grayish white, with brown edges. The old lesions have obvious concentric whorls, and a gray black mold like substance grows in the center of the lesion, which is the fruiting body of the pathogen.
The incidence pattern of tree peony wheel pattern spot disease:
The pathogen overwinters on the diseased remains and becomes a source of infection at the beginning of the following year. When conditions are suitable, it produces conidia, which spread through wind and rain, invading directly from wounds. The disease occurs from July to September, with the lower leaves first affected. In heavy rain, the disease becomes more severe.
Prevention and treatment methods for tree peony wheel pattern spot disease:
① Around early November (beginning of winter), sweep the leaves in the field and burn them together to eliminate pathogenic bacteria;
② Spray Bordeaux mixture 1:1:160 times before the onset of the disease (May), once every 10-15 days until the end of July;
③ In the early stages of the disease, spray 500-800 times the amount of methyl tobramycin and carbendazim once every 7-10 days for 3-4 consecutive times.
