虱螨脲亚致死剂量对棉铃虫生长发育和繁殖力的影响

用虱螨脲亚致死剂量处理棉铃虫1龄幼虫和3龄幼虫,结果表明:虱螨脲具有较强后效性,能降低棉铃虫化蛹率、羽化率、产卵量,提高畸形蛹、畸形蛾比例.1龄幼虫按0.1和0.2 mg/kg一次饲毒后,化蛹率分别为20.00%和15.50%,与对照相比显著降低;处理代雌、雄成虫羽化率分别下降6.50%、9.91%和18.48%、21.76%,雌、雄畸形蛾率分别上升15.61%、12.71%和27.55%、19.50%,产卵量下降34.06%和36.50%.第2、3代与第1代相比,化蛹率、羽化率、产卵量、卵孵化率逐渐有所提高,畸形蛹率、畸形蛾率降低,但与对照仍存在差异,表明虱螨脲对试虫的影响随世代延续而减弱,但至少可持续到第3代,且随用药剂量提高,其影响加大.与1龄幼虫饲毒结果相比,对3龄幼虫的影响程度相对较小,但趋势一致.

Lufenurons' Sublethal Effect on the Growth, Development and Fecundity of Helicoverpa armigera

Effects on the growth, development and fecundity by sublethal doses of lufenuron were investigated in the 1st instar and 3rd instar of Helicoverpa armigera Hübner.The results showed that lufenuron was an insecticide with long after effect, and the ratios of pupation, emergence, oviposition numbers of female, and egg hatch ability decreased, unhealt hypupa and adult rates increased after treaded with lufenuron.Compared with the CK, the pupation rates of the treated generation were 20.00%, 15.50% and decreased significantly; the emergence rates of male and female moths reduced by 6.50%, 9.91% and 18.48%, 21.76%; unhealt hy adult rates increased by 15.61%,12.71% and 27.55%,19.50% and oviposition numbers of female dropped by 34.06% and 36.50% after treatment 1st instar larvae with 0.1 and 0.2 mg/kg poisonous diet, respectively.Pupation rate, emergence rate, oviposition numbers of female and egg hatch ability of second, third generations were somewhat increased, and unhealt hypupa and adult rates dropped compared with the first treated generation, but they had difference significantly as compared to the CK.It indicated that influences of lufenuron on H.armigera were gradually weakened with the development of the generations, while such effects could last to the third generation after treatment at least and were obviously increased with higher dose.The influencing results on H.armigera of the experiments of feeding 3rd instar larvae on poisonous diet were slightly decreased,and the general variation trends were similar.