棉铃虫对拟除虫菊酯类杀虫剂抗性遗传力的分析

采用域性状分析法,估算了棉铃虫对氰戊菊酯、三氟氯氰菊酯和溴氟菊酯的抗性现实遗传力,并对3种菊酯的抗性风险进行了评估。结果表明,棉铃虫对氰戊菊酯、三氟氯氰菊酯和溴氟菊酯的抗性现实遗传力分别为0.2027、0.1554和0.1084。假设田间种群的抗性现实遗传力为估算值的一半,杀死率为80％,预计抗性增长到10倍时,氰戊菊酯可使用14次,三氟氯氰菊酯可使用19次,溴氟菊酯可使用31次。三氟氯氰菊酯和溴氟菊酯的抗性风险明显低于氰戊菊酯;棉铃虫对含氟菊酯的抗性发展速度明显低于不含氟的菊酯。试验结果为实际应用提供了理论依据。

REALIZED HERITABILITY OF RESISTANCE TO PYRETHROIDS IN HELICOVERPA ARMIGERA

Threshold trait analysis was used to estimate realized heritability(h2) of resistance to three pyrethroids and resistance risk in Helicoverpa armigera. The h2 of resistance to fenvalerate, cyhalothrin and flubrocythrinate were 0. 2027, 0. 1554 and 0. 1084 respectively. Assuming that h2 of field population was half of these values and that field population received prolonged and uniform exposure to pyrethroids causing > 80% mortality in each generation, substantially increased resistance to 10-fold would be expected after <14 generations for fenvalerate, <19 generation for cyhalothrin and < 31 generation for flubrocythrinate. Resistance risks to cyhalothrin and flubrocythrinate in Helicoverpa armigera were smaller than that of fenvalerate. Resistance development to pyrethroids with fluorine was smaller than pyrethroids without fluorine. These results provided theoretical basis for application.