Symptoms and prevention of anthrax

Orchid anthracnose: mainly harmful leaves, black-brown disease spots appear on the leaves at the beginning of the disease, and there is a faded green halo around. After enlargement, the lesion is oval or strip-shaped. The edge is dark brown, the interior is yellow brown, and the disease spot is slightly raised. In the later stage, black particles appeared on the disease spot, and the black particles extruded pink colloids under wet conditions, that is, the conidia disk and conidia pile of pathogens. Anthrax occurred for a long time, especially from July to August. Prevention and treatment: ① pay attention to ventilation and light transmission. ② fertilized reasonably, improved disease resistance, controlled the application of nitrogen fertilizer during the growing period, and applied more phosphorus and potassium fertilizer appropriately. At the initial stage of ③, 50% carbendazim or 70% topiramine wettable powder was sprayed 500-800 times.