How to prevent and cure lettuce brown spot?

How to control lettuce brown spot disease? Please introduce the control method lettuce brown spot disease mainly harm leaves, generally through seed disease and wind and rain transmission, spread, infection, poor plant growth or partial application of nitrogen fertilizer caused by excessive growth, will lead to the occurrence of aggravated disease. There are two kinds of symptoms: one is water stains at the beginning, and then gradually expands into round or irregular, brown to dark gray spots with diameters ranging from 2 to 10 mm. Another kind is dark brown disease spot, the edge is irregular, periphery has water stain shape halo. Damp spots on the surface of the Health dark gray mold, severe disease spots fuse with each other, to brown leaves dry. Control measures: 1. Clean the countryside, prepare the land in time, apply lime and organic base fertilizer after deep ploughing and drying. After harvesting, the sick and disabled bodies are taken out of the garden and burned in time, and disinfectant is sprayed to disinfect the whole garden, and 800 times of high lipid membrane solution is added to spray, so that the utilization rate of effective components of the pesticide is greatly improved. 2. During planting and management period, pay attention to reasonable irrigation, reasonable combination of nitrogen, phosphorus and potassium topdressing, and spray foliar fertilizer plus strong stem spirit to make plants grow healthily, improve resistance, make stems thick, leaves plump, fresh and tender, natural taste thick. 3. Chemical control: spray 75% chlorothalonil WP 1000 times solution and 70% thiophanate-methyl WP 1000 times solution at the early stage of disease to reduce the spread of brown spot disease, and spray new lipid membrane to form protective film to prevent bacteria from spreading by wind and rain. Spray once every 10 days or so for 2~3 times continuously. 5 - 7 days before harvest. Click for more lettuce growing techniques Click for more vegetable growing techniques