1. Symptoms: The disease first produces waterlogged spots around the lenticels on the pericarp of the diseased fruit, and when it is enlarged to 2mm, the center of the diseased spot turns brown, and finally a nearly round and dark purple lesion is formed, with waterlogged halo at the edge, slightly concave in the middle, rough surface hardening and irregular cracks, which can reach about 35 mm. When the humidity is high, the affected part may have a yellow wrist and the diseased fruit will fall off early. High temperature and high humidity are beneficial to bacterial infection and aggravate the condition. Orchards with weak trees, poor drainage and ventilation or too much nitrogen fertilizer are more seriously ill.

Second, the prevention and control methods:

1. Strengthen the comprehensive management of orchards, apply more organic fertilizers, and improve the disease resistance of trees.

2. Orchards with heavy soil and high groundwater level should pay attention to improving soil and drainage. Select and plant disease-resistant varieties, carry out reasonable shaping and pruning, and create good ventilation and light transmission conditions.

3. Cut off the diseased branches in winter, scrape off the diseased spots on the branches in early spring and smear the wounds with 25-30 degrees stone sulfur mixture to reduce the primary source of infection.

4. Chemical control: amobam, agricultural streptomycin, neophytomycin and thiram can be sprayed at conventional concentration, and the number of chemical control should be appropriately increased during the fruit growth period.