How do farmers use agricultural plastic covers to protect crops from pests and diseases?

Farmers use agricultural plastic covers, such as polyethylene film, to create physical barriers that protect crops from pests and diseases. These covers can prevent insects from reaching the plants, reducing the spread of diseases they may carry. They also help in maintaining a clean environment around the crops, which can limit the growth of pathogens. Additionally, plastic covers can regulate temperature and humidity, creating conditions less favorable for pests and diseases to thrive. This method is particularly effective in high tunnels and greenhouses, where the controlled environment can significantly reduce the need for chemical pesticides and fungicides, promoting sustainable agriculture.