How to use medicine to prevent tomato from growing "black hair"

In the early stages of the disease, symptomatic agents should be used early to prevent and control. (1) Smoke agent: use 250g of 45% chlorothalonil smoke agent per mu, divide the smoke agent into 4-6 piles, place them at a distance of 30cm from the plants, close the shed film in the evening, light the smoke agent (no open fire), retreat to the outside of the shed, close the shed door, close it overnight, and let out the air the next morning. Fumigate once every 7 days, continuously fumigate 2-3 times. (2) Dust spraying: 1 kg of 5% chlorothalonil dust per mu, or 1 kg of 7% Yemeijing dust per mu. In the sunlight greenhouse, the pesticide applicator faces south and sprays powder laterally along one end of the north wall of the greenhouse; in the greenhouse, the pesticide applicator retreats from one end of the middle walkway to spray powder, aims the powder spraying pipe at the upper part of the tomato plant, and swings left and right at a constant speed to make the dust agent evenly sprayed into the greenhouse space. Generally, about 200 grams of powder is sprayed every minute, and the side (retreat) line is 10-12 meters. After spraying the dust agent, the applicator exits the shed door and closes it overnight. Spray every 7 days for 2-3 times. (3) Spraying: In the morning of sunny days, spray 2% Wuyimycin aqueous solution 200 times, or 1:1:200 Bordeaux mixture, or 75% chlorothalonil wettable powder 500 times, or 50% prohydantoin wettable powder 1500 times, or 47% Duannong wettable powder 600-800 times, or 40% Fuxing emulsifiable concentrate 8000-10000 times, and spray on the back of leaves. Spray once every 7 days, continuously spray 2-3 times, do not spray on rainy days.