Botrytis cinerea (batryris elliptica cocke) of lily

Commonly known as lily leaf blight. Mainly damage leaves, but also infect stems, flowers, buds and bulbs. The disease spot on the leaf is round or oval, yellowish brown or reddish brown, the center of the spot is light yellow or light brown, and the edge is purplish red or light red. When the weather is wet, the disease part produces a gray mildew layer; when dry, the disease spot becomes thin and brittle, translucent, light gray. After the disease spot expands, the leaves wither and die, buds and flowers suffer, like boiling water scald, brown and rot. Stem damage, resulting in light brown ulcer spots, very easy to wind break. After infection, the young plants often cause the death of the growth point, and sometimes infect the bulb, which can make the bulb rot. Botrytis cinerea of lily mainly passes through the bad environment with sclerotia. Conidia are produced by sclerotia in spring and spread rapidly in the field by means of wind, rain and airflow. It started in early May and flourished from late May to late June. The temperature in this period is high, and if there is a long-term overcast and rain, the disease will accelerate the epidemic. Prolonged rain and thundershowers can promote the epidemic of the disease. The application of immature organic fertilizer, excessive nitrogen fertilizer and low-lying stagnant water are all beneficial to the disease.