梨星毛虫是苹果、梨等果树的主要害虫之一。此虫在我区发生较为普遍,而且危害严重,有些果园由于多年采用乐果或敌敌畏进行防治,因而产生了抗性,对果树的稳产高产有严重威胁。为了提高杀虫率和达到合理用药的目的,我们进行了马拉硫磷不同浓度的试验。 Pear is one of the major pests of fruit trees such as apples and pears. This pest occurred in my area is more common, but also endangered, and some orchards due to years of dimethoate or dichlorvos to prevent and control, resulting in resistance, a serious threat to the steady and high yield of fruit trees. In order to improve the insecticidal rate and achieve the purpose of rational drug use, we conducted different concentrations of malathion test.