Most vegetable farmers use their own years of experience to apply pesticides, rather than based on the occurrence and development of pests and diseases. For various diseases of vegetables and vegetables, whether it is fungal diseases, bacterial diseases, viral diseases or physiological diseases, we see that vegetables and fruits have slight changes and spray pesticides; for all kinds of vegetables and insect pests, whether it is by quail It is caused by maggots, and it doesn't matter if the medicines used can cure their worms. In fact, each pest has its own unique habits and hazards. For example, powdery mildew is easy to infect the young part of the vegetables, and black spot disease is easy to infiltrate from the lower leaves. The worms gather on the back of the leaves of vegetables and absorb vegetable juices. . Most of the pesticides used to prevent and treat diseases and pests are particularly strong in their specificity. They often target diseases caused by one or a certain type of pathogen and are ineffective against other diseases. Therefore, the application must be due to illness, due to pesticide application.
Some vegetable farmers have seen pests in the shed, and they will immediately spray pesticides to eliminate them completely. In fact, it is completely unnecessary. From an economic point of view, pests in sheds should not be controlled as long as they do not exceed prevention and control targets, otherwise they may reduce the output-to-output ratio.