Dongguan Anmeixuan Electronic Technology Co., Ltd , https://www.hyashine.com
Shed lettuce to prevent downy mildew
Lettuce downy mildew is the main disease before and during the growth of lettuce in greenhouse. The disease can be affected from the seedlings of lettuce to adult plants. The diseased leaves spread from the bottom upwards, with yellowish round or polygonal spots on the leaves at the onset of disease, and a white moldy layer growing on the lesions on the back of the leaves when wet. In severe cases, the lesions are divided into pieces and the whole leaf withers, thus affecting the yield. In the early stages of the occurrence of downy mildew in greenhouses, the prevention and control methods are as follows: First, to control the humidity in the greenhouse, open the ditch outside the shed, and close the shed in case of low temperature and rainy weather. When the humidity in the shed is high (fog in the shed), it is necessary to open the shed to reduce the temperature at noon. When the shed is too dry, drip irrigation or artificial watering may be used, and flooding of the shed is prohibited. The second is in the early stages of disease, using DuPont Kelu 800 times or 70% EDPH Mn Zn WP 500 times for spraying, disease prevention every 5 to 7 days 1 time, continuous control 2 to 3 times.