What is the disease caused by small holes on camellia leaves, and how to deal with it?

Red leaf spot disease

Causes and symptoms The disease is caused by fungi of the genus Phyllosticta sp. Lesions mostly occur on younger leaves and initially appear as light brown round stain-like spots. Later, the lesions spread and the color changes from light brown to tan. Sometimes multiple lesions merge into larger patches or spread throughout the leaves, causing a large amount of scorching and falling off of the leaves.

Pattern of incidence: The bacterium survives on the diseased remains of the host, and the spores are spread by wind, rain, running water, etc. The disease generally begins to occur in May, with the peak incidence occurring from July to September, and the affected leaves fall off in large numbers.

Prevention and treatment methods ① In the early stage of the disease, spray 70% thiophanate methyl 1 000 to 1 500 times solution or 25% sterilant 400 times solution for prevention and control. ②In times of drought, water spraying on the leaves can be increased to inhibit the occurrence of diseases.