抗高效氯氟氰菊酯甜菜夜蛾近等基因系的交互抗性和种群适合度

 测定了对高效氯氟氰菊酯不同抗性水平的近等基因系高抗种群（NILs-RR）和低抗种群（NILs-RS）对13种杀虫剂的交互抗性，结果表明高抗种群对高效氯氰菊酯、氰戊菊酯、高效氟氯氰菊酯、甲氰菊酯和溴氰菊酯的交互抗性倍数在15.2～92.6之间；对氟虫腈，阿维菌素、灭多威和甲胺基阿维菌素也存在14.1～67.5倍的较高交互抗性；而对毒死蜱、溴虫腈、虫酰肼及辛硫磷的交互抗性较低，在3.0～7.6倍之间。低抗种群对氟虫腈和阿维菌素存在较明显的交互抗性，在13.3～14.3倍之间；对高效氯氰菊酯、氰戊菊酯、灭多威、溴虫腈和甲胺基阿维菌素有一定程度的交互抗性（5.8～9.9倍）；对高效氟氯氰菊酯、溴氰菊酯和甲氰菊酯的交互抗性较低（2.6～2.9倍）；对辛硫磷、毒死蜱和虫酰肼则没有明显的交互抗性（1.7～1.8倍）。对构建的甜菜夜蛾敏感种群（SS）、近等基因系高效氯氟氰菊酯抗性种群(NILs-RR)和近等基因系低抗性种群(NILs-RS)生命表分析表明，以SS种群为参比，NILs-RS、NILs-RR种群的相对适合度分别为0.870、0.893，抗高效氯氟氰菊酯不同基因型甜菜夜蛾SS，NILs-RS和NILs-RR三种群净增殖率分别为624.7, 543.6和557.8，无显著差异，表明高效氯氟氰菊酯的抗药性未引发甜菜夜蛾适合度变化。综合上述研究结果可见甜菜夜蛾对高效氯氟氰菊酯产生抗药性后，与其它菊酯类药剂、氟虫腈和阿维菌素存在较高水平交互抗性，此类药剂间不宜混用或轮用；与辛硫磷、毒死蜱和虫酰肼的交互抗性均较低，可以混用或轮用。在高抗地区也可以通过引入敏感种群进行抗性稀释的方法治理甜菜夜蛾对菊酯类杀虫剂的抗性。

Cross-Resistance and Relative Fitness of Lambda-Cyhalothrin Resistant Near-Isogenic Lines in Spodoptera exigua (Hübner)

The cross-resistances to 13 insecticides in different resistant NILs-RR and NILs-RS strains of Spodoptera exigua to Lambda-cyhalothrin were determined in the laboratory. The results indicated that the high resistance strain (NILs-RR) showed a high level to all of the tested pyrethroids (15.2- to 92.6- fold), middle level to fipronil, abamectin, methomyl, and methylaminoavermectin (14.1- to 67.5-fold), and low level to chlorpyrifos, chlorfenapyr, tebufenozide and phoxim(3.0- to 7.2-fold). However, it was found that the low resistance strain (NILs-RS) possessed much high level to fipronil and abamectin (13.3- to 14.3-fold), moderate level to α-cypermethrin, fenvalerate, methomyl, chlorfenapyr and methylaminoavermectin (5.8- to 9.9-fold), and low level to beta-cyfluthrin, deltamethrin and fenpropathrin (2.6- to 2.9-fold). Relative fitness experiments for the populations of lambda-cyhalothrin-susceptible (SS), NILs-RR and NILs-RS strains of Spodoptera exigua, showed that relative finesses of NILs-RS and NILs-RR were 0.870 and 0.893, in comparison with that of SS strain. The intrinsic rates of natural increase of SS, NILs-RR and NILs-RS were 624.7, 543.6, and 557.8 respectively. There was no significant difference in the fitness between SS and different resistant lambda-cyhalothrin genotypes (NILs-RS and NILs-RR) of Spodoptera exigua. From the research, other pyrethroids, fipronil and abamectin are the high cross-resistance level insecticides to the lambda-cyhalothrin resistance of Spodoptera exigua, and couldn't be mixtured and rotated; But phoxim, tebufenozide and chlorpyrifos could be used with lambda-cyhalothrin for the lower cross-resistance risk. In the high lambda-cyhalothrin resistance level area, immigrated into the susceptible population maybe a good approach for resistance management.