草地贪夜蛾在安徽地区越冬能力初探

草地贪夜蛾的生长发育、繁殖和分布与环境温度密切相关,为探明该虫在安徽地区的越冬能力,本研究利用人工接虫的方式模拟草地贪夜蛾冬季的田间存活状态,调查幼虫存活率、龄期、植株被害率,并利用线性模型预测草地贪夜蛾田间发育历期。结果表明:草地贪夜蛾在田间平均气温低于10℃并持续8~10 d时死亡率达到100%;10月15日接入的草地贪夜蛾幼虫无法完成完整世代周期,但仍能为害玉米幼苗,接虫后30 d玉米植株的被害率均达100%;根据模型公式,采用10月15日至11月18日期间的温度预测发育历期,得到卵、幼虫、蛹以及整个世代的发育历期分别为9.23、46.86、40.70、69.38 d。本研究初步探明了草地贪夜蛾在安徽地区的越冬规律,研究结果为虫情监测和防控提供科学依据。

Potential overwintering ability of fall armyworm Spodoptera frugiperda (J.E. Smith) in Anhui province

The growth, development, reproduction and distribution of Spodoptera frugiperda are closely related to environmental temperature. In order to clarify the overwintering ability of the insect in Anhui, artificial inoculation was used to simulate the survival status of S.frugiperda in winter. The larval survival rate, age and damage rate to plant were investigated, and the linear development model was used to predict the field development duration of different instars. The results showed that the mortality was 100% when the average temperature was below 10℃ for 8-10 days. The larvae inoculated on October 15 could not complete the full generation cycle. However, they could still damage corn, and the damage rate was 100% 30 d post inoculation. According to the temperatures between October 15 and November 18, the predicted developmental duration of eggs, larvae, pupae and the entire generation was 9.23 d, 46.86 d, 40.70 d and 69.38 d, respectively. The results provided scientific basis for monitoring and control of insect pests.