1. Potential causes:
A. During the fruiting phase, partial-low temperature especially under 14 degrees Celsius.
B. Mushroom farmers spray water to the surface of mushroom or too high environmental humidity. Condensate water accumulation on cap surface results in the phenomenon of knots.
In a word, when you cultivate King oyster mushrooms, control the temperature of mushroom house in a range of 15-16 degrees Celsius, particularly eliminate large temperature difference between day and night so that you prevent condensate water on cap surface. In the meantime, be sure to eradicate too high environmental humidity on mushroom house and direct water-spraying on cap surface.