Prevention and cure method

1. Water accumulation should be avoided in potted plants for horticultural control, and humus fertilizer and potassium fertilizer should be added to improve disease resistance. The diseased plants should be removed in time and the diseased leaves should be removed in winter to feed the source of infection.

2. chemical control? At the onset stage, Bordeaux mixture with lime dosage of 1: 2: 100 can be sprayed at the initial stage, and then 1000- 1500 times of 50% benomyl wettable powder solution or 800- 1000 times of 50% carbendazim can be sprayed.