农药的使用是农作物病、虫、草、鼠害防治的重要措施，可实际上，喷撒出去的农药只有极少部分能达到防治靶标上，Ｍｅｔｃａｌｆ（１９８０）估算，从施药器械喷撒出去的农药只有２５％～５０％能沉积在作物叶片上，不足１％沉积在靶标害虫上，只有不足 ０．０３％的药剂能起到 The use of pesticides is an important measure for the prevention and control of crop diseases, insects, grasses and rodents. In fact, very few pesticides sprayed can reach the target of prevention and treatment. Metcalf (1980) estimated that spraying pesticides Of pesticides only 25% to 50% can be deposited on crop leaves, less than 1% deposited on target pests, only less than 0.03% of the agent can play