The high temperature and rain in summer is the peak period of migratory pests such as migratory locusts, aphids, and leaf miners, and rain and these migratory pests are also vectors of viral diseases, which brings about the cultivation and management of summer vegetables. Great difficulty. Under normal circumstances, the probability of infecting vegetables in summer vegetables is 60%-100%, and examples of vegetables that are not harvested due to viral diseases often appear in production. If we can cultivate vegetables and succeed at the peak of viral disease, we will greatly increase economic efficiency.
In the summer, using the winter period of the greenhouse to cover it and planting vegetables, it can avoid the large area of ​​virus disease. If the greenhouse does not remove the old film from the previous year, the sagging film around the shed can be taken up for ventilation. Throw some fresh grass on the film and shade the leaves to prevent heat. Then the gauze around the greenhouse can prevent whitefly, aphids, leafminers, and thrips from flying in and cut off the transmission of viral diseases. In this way, vegetables that are cultivated in summer can be sprayed only once or twice with pesticides to avoid the occurrence of viral diseases.