鳢肠乙醇粗提物与Cry1Ca的协同增效及对甜菜夜蛾SeABCC1―SeABCC3 mRNA表达量的影响

本试验旨在明确鳢肠Eclipta prostrata乙醇粗提物与Bt毒素Cry1Ca防治甜菜夜蛾Spodoptera exigua的协同增效作用,及对甜菜夜蛾转运蛋白C(SeABCC1―SeABCC3)m RNA表达量的影响。结果表明,鳢肠乙醇粗提物对甜菜夜蛾2龄幼虫具有明显毒杀作用,喂食5.26 mg/cm2鳢肠乙醇粗提物7 d后,幼虫死亡率为58.4%;喂食鳢肠乙醇粗提物(LD_(30))与Cry1Ca(LD_(30))混合物3、5和7 d死亡率分别为59.72%、73.61%和83.33%,但仅喂食Cry1Ca(LD_(30))死亡率分别为5.6%、13.9%和31.9%,仅喂食鳢肠乙醇粗提物(LD_(30))死亡率分别为21.8%、28.7%和30.1%,鳢肠乙醇粗提物与Cry1Ca的协同增效作用显著;qPCR分析SeABCC1―SeABCC3 mRNA表达量变化,经鳢肠乙醇粗提物(LD_(30))处理后SeABCC1、SeABCC2和SeABCC3表达量升高,引起甜菜夜蛾幼虫对Cry1Ca的敏感性升高。综上所述,鳢肠乙醇粗提物可作为植物源农药与Bt毒素混配使用,提高对甜菜夜蛾的防治效果。

Synergism between Crude Ethanol Extract of Eclipta prostrata with Cry1Ca and Its Influence on the Expression of ATP-binding Cassette Transporters C mRNA in Spodoptera exigua

The objective of this study was to determine the synergistic effect of crude ethanol extract of Eclipta prostrata (CEEEP) on toxicity of CrylCa against Spodoptera exigua and the changes of expression of SeABCC1,SeABCC2 and SeABCC3.The results showed that CEEEP had an obvious poisoning effect on the 2nd instar larvae ofS.exigua.When fed 5.26 mg/cm2 of CEEEP for 7 days,the mortality rate was 58.4％.When S.exigua ingested the admixture of LD30 of CEEEP and CrylCa,larval mortalities were 59.72％,73.61％ and 83.33％ after 3 d,5 d and 7 d.However,with LD30 of CrylCa alone,the mortalities were 5.6％,13.9％,31.9％,respectively,and with CEEEP alone,the mortalities were 21.8％,28.7％,30.1％,respectively.The relative expression levels of SeABCC1,SeABCC2 and SeABCC3 were analyzed by qPCR,CEEEP can induce high expression of SeABCC1,SeABCC2 and SeABCC3,causing the larvae ofS.exigua more susceptibility to CrylCa.In summary,CEEEP as botanical pesticide can be mixed with Bt toxin,to improve the control effect against S.exigua.