灰飞虱和白背飞虱雌雄成虫对杀虫剂敏感性的差异研究

采用稻苗浸渍法分别测定了6种常用杀虫剂对灰飞虱Laodelphax striatellus和白背飞虱Sogatella furcifera雌雄成虫的生物活性,以期明确这2种稻飞虱对杀虫剂敏感性的性别差异。结果显示,烯啶虫胺对灰飞虱和白背飞虱雌成虫的LC50分别是其雄成虫的2.88倍和3.09倍,说明雄成虫对烯啶虫胺的敏感性均高于雌成虫。三氟苯嘧啶对灰飞虱雌成虫的LC50是其雄成虫的1.79倍。2种飞虱雌雄成虫对其他几种药剂的敏感性无显著差异。2种飞虱的雌成虫体型均大于雄成虫,灰飞虱和白背飞虱雌成虫体重分别是雄虫的1.88倍和1.85倍。综上,灰飞虱和白背飞虱成虫对烯啶虫胺和三氟苯嘧啶的敏感性存在性别差异,但个体大小差异并不是雌雄虫对杀虫剂敏感性不同的唯一原因。

Insecticides susceptibility difference in female and male adults of Laodelphax striatellus and Sogatella furcifera

Bioassay of six commonly used insecticides for controlling rice planthopper the male and female adults of Laodelphax striatellus and Sogatella furcifera was measured using rice seedling immersion method, in order to clarify the susceptibility differences to insecticides between female and male adults in these two rice planthoppers. The results showed that the LC50 values of nitenpyram to female adults of L.striatellus and S.furcifera were 2.88- and 3.09-folds higher than those of male adults, respectively, indicating the susceptibility of male adults of L.striatellus and S.furcifera to nitenpyram was higher than that of female adults. Besides, the LC50 value of triflumezopyrim to the female adult of L.striatellus is 1.79-fold than that of male adult. In addition, there was no sex difference in the susceptibility of these two rice planthoppers to other insecticides. Moreover, the female adults of both rice planthoppers have larger body size than that of male adults. The female adult body weight of L.striatellus and S.furcifera was 1.88- and 1.85-folds than that of male adult, respectively. In summary, there are sex differences in the susceptibility of L.striatellus and S.furcifera adult to nitenpyram and triflumezopyrim, but individual size differences are not the only reason for the different susceptibility of male and female insects to insecticides.