灰茶尺蠖的生物学特性

灰茶尺蠖（Ectropis grisescens Warren）在中国广泛分布，是茶树主要害虫之一。通过田间调查和室内观测，研究了灰茶尺蠖的形态特征、年生活史、生活习性和种群生命表。结果表明：灰茶尺蠖在浙江新昌地区年发生6～7代，第1代幼虫出现在3月下旬至4月下旬，以后约每月发生一代，10月中下旬陆续开始以蛹在茶树根际土壤中越冬，翌年3月中旬羽化。灰茶尺蠖幼虫4～5龄，总食叶量平均736.2 mg·头－1，3龄后食叶量总计占96.01%，各龄食叶量呈指数增长，食叶量（y）与虫龄（x）的指数曲线为y = 1.012e1.5857x。在室内饲养条件下，灰茶尺蠖每雌平均产卵2910粒，卵、1～3龄幼虫、4～5龄幼虫、预蛹、蛹和成虫的存活率分别为93.8%，98.6%，98.6%，98.6%，82.2%和92.0%，雌雄性比为1∶0.85，种群增长指数为98.9。

Biological characteristics of Ectropis grisescens Warren

Ectropis grisescens Warren was one of the major pests of tea plant， which widely distributed in China. The morphological characteristics， life history， life habit and population life table of E. grisescens were investigated in this paper based on field investigation and laboratory observation. Results showed that E. grisescens occurred 6-7 generations per year in Xinchang， Zhejiang province. The first generation of larvae occurred from late March to late April， and others occurred monthly. The pupae gradually began to overwinter in rhizosphere soil of tea from mid to late October and feathered in mid March of the following year. The larvae had 4-5 instars. The total amount of food consumption was 7362 mg per larva on average， and 9601% was eaten by instar from 3rd to the last. The food consumption of larvae exponentially increased from 1st to last instar， and the exponential curve between food consumption（y） and larva instar（x） was y = 1.012e1.5857x. Under the condition of laboratory， the number of eggs was 2910 per female. The survival rates of each stage of E. grisescens were as follows. eggs， 93.8%; 1st -3rd instar larvae， 98.6%; 4th -5th instar larvae， 98.6%; prepupae， 98.6%; pupae， 82.2%; and adults， 92.0%. The F1 generation sex ratio （♀∶♂） was 1∶0.85， and the population trend index was 98.9.