长春地区大菜粉蝶生物学特性观察

Biological characteristics of Pieris brassicae(Lepidoptera:Pieridae)in Changchun

大菜粉蝶Pieris brassicae是十字花科蔬菜上的重要害虫之一。本文通过田间观察结合室内饲养,系统描述了该虫各发育阶段的形态特征,记录了发育历期、生活史及其生活习性。大菜粉蝶在长春地区1年发生3代,以蛹越冬。成虫多产卵于叶背面,每块卵10~207粒。幼虫5个龄期,群集为害,随着幼虫龄期的增长,头壳宽度与体长逐渐增加,各龄期头壳宽度和体长生长模型为:y_(W)=1.727e^(0.557x)(R^(2)=0.998)和y_(L)=0.031 x^(2)+0.339 x-0.013(R^(2)=0.994)。取食白菜、油菜、甘蓝和萝卜4种寄主的幼虫发育历期存在显著差异,取食白菜发育最快,取食油菜的蛹最重,白菜和油菜更适宜其生长发育。本研究描述了大菜粉蝶各发育阶段的形态特征,明确了其主要生物学特性,为该害虫的识别监测和综合防控提供了理论基础。

Pieris brassicae is one of the most important pests of cruciferous vegetables.The morphological characteristics,developmental duration,life cycles and the habits of various developmental stages of P.brassicae were investigated in the field and laboratory.Three generations of P.brassicae were observed per year in Jilin province and overwintered mainly as a pupa.Females laid eggs on the back of leaf,and the number of eggs per mass varied from 10 to 207.The larvae had five instars,feeding on the host plant in a clustered way.Both head width and body length increased with increasing instar,head width:y_(W)=1.727e^(0.557x)(R^(2)=0.998);body length:y_(L)=0.031 x^(2)+0.339 x-0.013(R^(2)=0.994).The developmental durations of P.brassicae larvae feeding on Chinese cabbage,rape,cabbage and radish showed significant differences.The shortest duration was observed on Chinese cabbage,and the heaviest pupae were recorded on rape.These results indicated that the Chinese cabbage and rape were beneficial to the development of P.brassicae.This study preliminarily clarified the morphological and biological characteristics of different developmental stages of P.brassicae,which helps in the identification of P.brassicae in the field and provides some crucial information for developing control and prevention strategies.