Symptoms of tobacco anthracnose?

Update Date: 2023-01-05 Source: Network

summary

Tobacco anthracnose is caused by the infection of a fungus belonging to the genus hydatidosis. Tobacco anthracnose was first reported by Brazil in 1922. It was also found in Germany, Japan, the United States, China, Australia, India, North Korea and Africa. The disease can occur in all growth stages of tobacco, but it is common and serious in seedling stage. The leaves of seedlings are densely covered with disease spots, and the whole tobacco seedling is often destroyed when the disease is serious. Generally, although the seedlings are not destroyed when the disease is serious, the seedling growth is poor, and it can continue to damage after transplanting in the field, resulting in greater losses. The occurrence of anthrax has seriously affected the economic benefits of tobacco planting. Symptoms of tobacco anthracnose? Let's talk about it

Symptoms of tobacco anthracnose?

The pathogen overwinters in soil and fertilizer with the remains of diseased plants. It can also infiltrate into the seeds or adhere to the surface of the seeds with conidia, becoming the source of the disease at the beginning of the next year.

After the disease occurred in the seedbed, the disease also occurred in the transplanting field, mostly in the bottom leaves. The conidia produced on the diseased tissues were reinfected by wind and rain. The temperature of 25-30 ℃ is the most suitable for the disease.

Water plays a key role in the propagation and transmission of the pathogen. The conidia adhering to the conidial disk are splashed and dispersed by rain or irrigation, and germinate and infect under the condition of water film on the leaf surface.

matters needing attention

Before the onset of the disease, 1; 1: 160 ~ 200 Bordeaux solution for prevention. After the onset of the disease, 50% can be used to spray 500 times of COPD wettable powder or 480 of oxy mycin 480. If it can reach more than 90%, it can also use 50% times of 800 times wetting powder, or 75%% chlorothalonil wettable powder, or 50%% of zinc, 80% anthracnose, or 50%.