草地贪夜蛾在不同温度条件下的生长发育特性

为掌握草地贪夜蛾的主要生物学特性,本文在5个恒温条件下:20℃、25℃、28℃、32℃和35℃,采用玉米苗作为饲料,测定了不同虫态的发育历期、繁殖力、发育起点温度和有效积温。结果表明:在20~35℃温度条件下,草地贪夜蛾的发育历期随着温度的升高逐渐下降,完成一个世代发育历期在23.0~48.3 d;其中,卵、幼虫、蛹、成虫和世代发育起点温度分别为:12.70℃、11.11℃、11.01℃、5.65℃和9.21℃,有效积温分别为:39.40日·度、201.25日·度、134.12日·度、171.06日·度和636.53日·度;20~32℃是卵、幼虫、蛹和成虫产卵的适宜温度,15℃、35℃恒温条件下不适宜草地贪夜蛾的生长发育。根据本试验测定的发育起点温度与有效积温,推测草地贪夜蛾在滇中、滇西、滇南、滇东南、滇西南、滇东北、滇西北年发生世代分别为2.18~8.59代、2.28~10.15代、3.43~12.13代、3.15~8.46代、2.75~9.39代、1.38~6.87代、1.11~6.72代。

The growth and development characteristics of Spodoptera frugipetda under different temperature conditions

In order to study the main biological characteristics of Spodoptera frugipetda,the developmental duration,fecundity,developmental threshold temperature and effective accumulated temperature of different stages were measured on maize seedlings were used as feed under five temperature conditions:20℃,25℃,28℃,32℃and 35℃,in laboratory.The results showed that the development duration of S.frugipetda(egg,larvae,pupae and adult)was gradually decreased with the increase of temperature within the range from 20℃to 35℃,and the generation development duration was 23.0~48.3 d.The developmental threshold temperatures of egg,larvae,pupa,adult and whole generation were 12.70℃,11.11℃,11.01℃,5.65℃and 9.21℃,respectively.And the effective accumulate temperatures were 39.4 d·℃、201.25 d·℃、134.12 d·℃、171.06 d·℃and 636.53 d·℃.The optimum temperature for eggs,larvae,pupa developing and adults oviposition was 20~32℃.However,the temperature of 15℃and 35℃were not conducive to S.frugiperda growth and development.Base on the tested developmental threshold temperature and effective accumulative temperature,the paper speculated that the generation numbers of S.frugipetda in the middle regions,west,south,southeast,southwest,northeast and northwest were 2.18~8.59,2.28~10.15,3.43~12.13,3.15~8.46,2.75~9.39,1.38~6.87 and 1.11~6.72 respectively in Yunnan Province.