一是“识药关”。熟悉农药主要品种的性能、特点、防治对象和使用范围,是正确用药降低农残的保证。二是“适时关”。要根据病虫害发生规律和危害程度,确定防治时期。防治虫害,应在成虫产卵高峰期或幼虫卵孵化期进行,因为三龄前幼虫集中、体小、抗药力弱。因此,抓住卵孵化盛期至幼虫三龄前喷药最为适时。防治病害,应在病菌孢子萌发期,即发病前和发病初期喷药最好。三是“适量关”。配药过多,不仅发生药害,加大成本,造成浪费和污染,而且会使病虫害加大抗药 First, “know medicine off ”. Familiar with the performance of the main varieties of pesticides, characteristics, prevention and treatment of the use of the scope of the correct use of pesticides to reduce pesticide guarantee. Second, “timely clearance ”. According to the law of pests and diseases and the degree of harm, to determine the control period. Pest control should be in the peak of oviposition or larval egg hatching period, because before the third instar larvae concentrated, small, weak resistance. Therefore, grasping the peak of egg hatching until the third instar larvae spraying the most timely. Disease prevention and control, should spore germination of the bacteria, that is, before and during the onset of the best spraying. Third, “appropriate amount off ”. Too much dispensing, not only phytotoxicity, increased costs, resulting in waste and pollution, but also will increase pest and disease resistance