温度对小菜蛾成虫繁殖和寿命的影响

为了对小菜蛾 (Plutella xylostella L.)发生为害的种群动态规律提供参考。研究了5种恒温对小菜蛾实验种群的存活，繁殖与寿命的影响。结果表明：在15、20、25、30、35℃的范围内，小菜蛾的产卵前期和历期随着温度的升高而缩短。在35℃高温下，37.5%的小菜蛾雌虫不孕，且正常雌虫的产卵量显著减少，仅为75.7粒/雌，说明持续高温对小菜蛾成虫的产卵是不利的。小菜蛾的繁殖动态也随着温度不同而不同，小菜蛾雌虫的卵峰日都在开始产卵的3日内，累积产卵量达总卵量80%的雌虫日龄随着温度的升高而缩短。小菜蛾雌虫的寿命也随着温度升高而明显缩短，两者呈显著性负相关(r=-0.981，P<0.05)。

Effects of Temperature on Oviposition and Longevity of Adult Diamondback Moth (Plutella xylostella L.)

Oviposition and longevity of the Diamondback Moth, Plutella xylostella L. at 15, 20, 25, 30, 35℃ temperatures were monitored in laboratory experiments. The mean preoviposition and oviposition periods were in negative relation to temperature. The mean number of eggs laid by moth decreased dramatically and 37.5% adult females failed to oviposit at 35℃, compared to other tested temperatures. Eighty percent of total eggs were laid in the first 3 days after the moths beginning to oviposit at each temperature, and the period of time for so many eggs to be laid became shorter with temperature increasing. Longevity of the adult females of the moth decreased from 46.4 days at 15℃ to 3.6 days at 35℃, negatively correlating with temperature (r=-0.981, P<0.05). Based on the above results, patterns of population dynamics of the diamondback moth were discussed.