农药出厂时间长或贮存保管不当,容易变质失效.施用失效的农药,不但达不到防治病虫害的目的,还造成一定的经济损失和人力上的浪费。那么,怎样鉴别农药是否失效呢?1、粉剂农药如2.5%敌百虫粉、3%硫特普粉、1.5%甲基对硫磷粉、5%多菌灵粉剂等,如果粉剂已经结块,说明药剂受潮分解,一般都失效了. Pesticide factory for a long time or improper storage, easy to spoilage failure.Application of pesticides failed, not only to prevent the purpose of pests and diseases, but also cause some economic losses and human waste. So, how to identify whether the failure of pesticides do? 1, powder pesticides such as 2.5% trichlorfon powder, 3% sulfur special powder, 1.5% methyl parathion, 5% carbendazim powder, , Indicating that chemicals damp decomposition, are generally ineffective.