不同温湿度条件下飞虱虫疠霉对桃蚜生殖力和内禀增长力的影响

Effects of Pandora delphacis on the fecundity and innate capacity for increase of Myzus persicae at different temperatures and relative humidities

对 7日龄桃蚜Myzuspersicae用高剂量飞虱虫疠霉Pandoradelphacis接种后 ,饲养于不同温 (10～ 30℃ )、湿 (74%～10 0 %RH)度组合条件下观察其生殖力及内禀增长力 (rm)的变化。结果表明 ,被接种个体生殖力比对照显著降低 ,且下降幅度受温度、湿度及温湿互作的影响。在各处理组合中 ,尤其以 2 0～ 30℃和 95 %～ 10 0 %RH的条件下下降更为明显。各处理rm 在不同温度间差异显著 ,均随温度呈抛物线形变化 ,2 5℃下达最高 ,但不同湿度间差异不显著。与对照相比 ,被接种蚜的rm 除 10℃与各湿度组合间无显著差异外 ,其余温湿组合下均显著低于对照。上述分析表明 ,飞虱虫疠霉的侵染能显著影响桃蚜生殖力及rm。

The effects of Pandora delphacis infection on the net reproduction rate (R 0) and innate capacity for increase (r m) of the green peach aphid, Myzus persicae were investigated. Seven day old nymphs inoculated with the fungal conidia at a dosage higher than LD 50 were maintained on the Chinese cabbage, Brassica olerracea, at temperatures of 10～30℃ and relative humidity (RH) of 74%～100%. The results indicated that number of nymphs produced by the treated aphids was significantly less than those produced in control, especially at higher temperatures (20～30℃) and RHs (95%～100%). Their r m differed greatly among the temperatures tested, showing a parabolic curve with the peak at 25℃. No significant effect of RH on their r m was detected. The inoculated aphids at 15～25℃ had an innate capacity for increase significantly smaller than those in control. These results suggested that P.delphacis be a potential microbial agent against the aphid.