山东省农业科学院植物保护研究所近期提出一种二点委夜蛾幼虫虫龄的测定方法。二点委夜蛾属鳞翅目夜蛾科,我国于2005年7月在河北省夏玉米田首次发现。近年来,该虫发生范围不断扩大,为害日益加重,因此应制定科学有效的防治策略。幼虫的虫龄和龄期测定是害虫预测预报以及制定科学防治策略的重要依据。研究人员通过测量二点委夜蛾幼虫头壳宽度、体长、体重,对幼虫虫龄的划分进行了研究。根据所测数据的频次分布 Institute of Plant Protection, Shandong Academy of Agricultural Sciences recently proposed a method of determination of larvae of the 2nd instar Spodoptera litura. Two members of the armyworm Lepidoptera Noctuidae, China in July 2005 in Hebei Province, the first discovery of summer corn fields. In recent years, the scope of its occurrence has been expanding and the damage has been aggravated. Therefore, a scientific and effective prevention and control strategy should be formulated. Insect pest age and age determination of pest forecasting and development of scientific control strategy an important basis. Researchers measured larvae of the 2nd instar larvae by the head shell width, body length, body weight, larvae of insect age division were studied. According to the frequency distribution of the measured data