Anthracnose of leek

Anthracnose is an important disease of leek, which is widely distributed and common. The occurrence is usually very light and has no obvious impact on production, only when there are more Rain Water in a few plots or planting period, the disease is serious, 100% of the plants are infected, and some leaves die because of the disease, which obviously affects the yield and quality.

[symptoms] the disease mainly affected leaves and leaf sheaths. At the initial stage, white dots appeared on the surface of leaves or leaf sheaths, then developed into nearly oval to long fusiform or irregular white necrotic spots, and the boundary between the disease and health was obvious. Finally, black spots were produced on the surface of the disease spots, that is, conidium disks. When the disease is serious, the disease spots on the leaves are densely covered, and they are connected to each other, which causes the leaves to die in a short period of time.

[incidence regularity] the pathogen overwintered in the soil with the conidium or conidium, or the hyphae with the disease residue. When the conditions are suitable, the conidium disk produces conidia and forms infection. After the disease, the disease spread by Rain Water spatter and watering. The development temperature of the pathogen is 4 ℃ 34 ℃, the optimum temperature is about 20 ℃, and the suitable temperature is 20 ℃ for spore germination. During the growing period, the disease occurred when the air was moist for 32 ℃, and it was the most suitable for the disease at 26 ℃. During the production period, it was rainy, or the disease of poor drainage in the field occurred seriously.

[prevention and control methods] 1. Thoroughly remove the diseased and disabled tissue after harvest, plough the land in time, and reduce overwintering germs. 2. Rotation with non-onion and garlic for more than 2 years. 3. Drug control was carried out in the early stage of the disease. You can choose 25% Spock wettable powder 800 times liquid, or 25% Citalin wettable powder 500 times liquid, or 70% methyl thiophanate wettable powder 600 times liquid, or 40% polysulfide suspension 500 times liquid, or 2% agricultural antibiotic 120 water agent 200 times liquid spray or root watering.