Control of white silk disease of orchid

Orchid white silk disease generally harms the base of orchid leaves near the soil. At the initial stage of the damage, the injured part turned brown, showed water stains, gradually rotted and softened, and was easy to break. In severe cases, the pseudobulb was also infected and produced white sericeous mycelium. The sclerotia of the disease was rapeseed-like, first white, then yellow, and finally brown.

Orchid white silk disease should be controlled mainly by manual control, supplemented by chemical control. The specific methods are as follows: first, timely removal of diseased leaves, extraction of diseased plants and centralized destruction. The second is to strengthen ventilation between plants, plants should not be too dense. The third is to strengthen the management of fertilizer and water. Rain Water should be avoided to sprinkle directly on the orchid seedlings in the rainy season, and rain shelter cultivation is an important measure to prevent the occurrence of white silk disease. Watering should follow the principle of "no dry, no watering, watering thoroughly" to keep the basin soil moist and not wet. Fourth, it is appropriate to choose fully mature humus soil to prevent the breeding of bacteria. The soil should be sterilized at high temperature before use, or sterilized with 0.2% pentachloronitrobenzene. Fifth, in the plant disease, spray 25% trichlorothalonil or 75% chlorothalonil 600 times to 800 times, once every 7 to 10 days, 2 to 3 times in a row.