二点委夜蛾形态特征及生物学特性

二点委夜蛾是近年来我国夏玉米上发现的一种新害虫，目前在我国玉米产区有加重为害和成灾的趋势。为便于田间准确识别该虫、调查其发生为害规律以及掌握其主要生物学特性，在室内对二点委夜蛾不同发育阶段的形态特征和主要生物学特性进行了系统观测。结果表明，在温度为(26±1)℃、相对湿度70%左右、光周期L14 h∥D10 h、人工饲料饲养条件下，二点委夜蛾卵期平均为4.25 d；幼虫一般为5龄，幼虫期平均为18.28 d；蛹期平均为7.69 d，蛹重平均可达75.77 mg；成虫产卵前期平均为3.29 d，产卵可持续9.13d，平均每雌产卵量为305.3粒，最多产500粒，最少132粒。雌雄蛾平均寿命分别为14.75 d和18.88 d。整个世代发育历期约为33.35 d。

Morphological and biological characteristics of Athetis lepigone

Athetis lepigone, a new lepidopteron insect pest occurs in the summer corn in China in recent years, inflicts more severe damage to corn plants presently. To facilitate identification of the species, and investigation on the population occurrence and damage regularity, morphological and biological characteristics of the species were systematically observed at (26±1)℃, 70% RH and L14 h∥D10 h in the laboratory. The results showed that the mean incubation period of the eggs was 4.25 days. Larvae usually experience five instars, and the mean larval period was 18.28 days. The average pupal period and pupal weight were 7.69 days and 75.77 mg respectively. The Pre oviposition period and oviposition period of adults were 3.29 days and 9.13 days respectively. The maximum and the minimum total number of eggs laid per female in lifetime were 500 and 132 eggs respectively, with the average 305.3 eggs. Longevity of female and male was 14.75 and 18.88 days respectively, and the whole generation duration of the species was 33.35 days.