Control of Cymbidium blight

Cymbidium blight is one of the common diseases of Cymbidium, which mainly harms the leaves of Cymbidium.

Symptoms:

The newborn light reddish brown oval stripe spot, the surrounding tissue turns yellow, the disease and health boundary is obvious. In the later stage, it expanded into irregular large patches, and the disease produced small black-brown spots, that is, the conidium of the pathogen.

Disease characteristics: Cymbidium blight is a disease caused by fungi. The pathogen is daffodil polysporum. The pathogen overwintered on the diseased plant or in the soil with the diseased residual leaves, and the conidia were transmitted by wind and rain in the spring or autumn of the second year, and could spread at any time in the greenhouse. After the spores fell on the leaves, the spores germinated and invaded and the disease occurred after a few days of incubation. In the warm and rainy season, conidia are produced for re-infection. The disease is easy to occur under the conditions of high temperature, high humidity and sprouting or basin soil is too wet, and the disease is serious when partial or over-application of nitrogen fertilizer is applied.

Prevention and control methods:

(1) Horticultural control: timely removal of diseased leaves; appropriate application of potash fertilizer; avoid excessive watering and prevent moisture retention.

(2) Chemical control: spraying at the initial stage of the disease, the medicament can be 1000 times the solution of 50% carbendazim wettable powder, 25% carbendazim (bromazonitrile) wettable powder, 15% imidazole wettable powder 3000 times, 40% Fuxing (flusilazole) EC 70008000 times.