Mosaic disease of dancing lady orchids and methods for controlling edible fungus diseases

Symptoms: At first, pale yellow discontinuous streaks form along the leaf veins, often appearing mosaic-like. Then part of the mesophyll cells in the diseased spots necrose, forming brown necrotic spots with sunken surfaces. The pathogens are several viruses including Cymbidium mosaic virus (CyMV) and ColMV. The main route of transmission is sap transmission.

Control methods:

1. The greenhouse should be reasonably ventilated to avoid high temperature and high humidity; pay attention to drainage, and appropriately increase the application of phosphorus and potassium fertilizers; promptly remove diseased leaves, diseased fruits and residual plants.

2. Spray promptly at the early stage of disease onset: commonly used agents include 50% thiophanate-methyl wettable powder at 500 times dilution, or 80% Daconil wettable powder at 500 times dilution, or 75% chlorothalonil wettable powder at 600 times dilution, 50% carbendazim-thiram at 400 times dilution, or Bordeaux mixture at 1:1:200. Spray once every 7~10 days, for a total of 2~3 times.