Prevention and treatment of virus disease of lettuce with stunted growth and bad death spots

Lettuce virus disease can occur in both seedling stage and adult stage of lettuce. The main symptoms are mosaic, deformity, yellow flower, dwarfism, necrosis, etc., and the diseased plant is dysplastic. At the initial stage of the disease, lettuce leaves showed light green or yellow-white irregular mottled, irregular leaf margin, and appeared missing. In the later stage, yellow-green mottled or not obvious brown necrotic spots and mosaic gradually appeared, and the yield and quality of lettuce decreased seriously.

Lettuce virus disease

Prevention and control measures:

1. Reasonable crop rotation, selecting lettuce varieties with strong disease resistance, weeds in the field, land and surrounding areas should be eradicated in time, and disinfection treatment should be carried out by spraying disinfectants and new high-fat film on the soil surface to establish disease-free remaining fields. Before sowing, base fertilizer should be fully applied and bottom water should be irrigated.

2. Strengthen field management, during the growing period of lettuce, timely ploughing and weeding, moderate watering, reasonable topdressing, increasing phosphorus and potassium fertilizer to improve disease resistance of lettuce; in the rosette stage and stem expansion of lettuce, each applied quick-acting nitrogen fertilizer and trace potassium fertilizer, combined with spraying Zhuangtuanling to make the stem of lettuce stout, luxuriant plants, strong natural taste and improve the ability of disaster resistance. Reduce residual toxicity for synergistic pesticides and fertilizers.

3, chemical control, lettuce virus disease in the initial stage, according to the requirements of plant protection, spraying 20% virus A wettable powder (or potassium permanganate 1000 times liquid, 5% bacterial dehydrated agent), combined with spraying new high-fat film to enhance drug efficacy, improve the utilization rate of effective ingredients, and consolidate the prevention and control effect.