噻虫嗪对白背飞虱试验种群繁殖力的亚致死效应

Sublethal effects of thiamethoxam on the fecundity of lab populations of white-backed planthopper Sogatella furcifera(Horváth)

为探究噻虫嗪对白背飞虱的亚致死效应,采用稻茎浸渍法以噻虫嗪亚致死浓度LC_(10)和LC_(25)胁迫白背飞虱3龄若虫,测定了F_0代和F_1代若虫的存活率、雌成虫寿命和产卵量,并组建了F_1代种群相对适合度生命表。结果表明,经噻虫嗪亚致死浓度胁迫后,F_0代白背飞虱若虫的发育历期延长,存活率降低,并且LC_(10)处理组的F_0代雌成虫寿命比对照组显著延长,而成虫产卵量无显著变化;F_1代的若虫发育历期比对照组显著延长,且产卵量有所减少,LC_(10)处理组雌成虫产卵量比对照组减少了22.24,LC_(25)处理组比对照组减少了69.96,且差异显著;LC_(10)和LC_(25)亚致死浓度处理后F_1代的种群增长趋势指数均下降,种群相对适合度分别下降了0.12和0.36。研究表明,噻虫嗪亚致死浓度胁迫均可抑制白背飞虱的种群增长。

To figure out the sublethal effects of thiamethoxam on white-backed planthopper Sogatella furcifera（Horváth）, the 3rd instar nymphs were exposed to the two sublethal doses LC_（10） and LC_（25）of thiamethoxam with the rice stem dipping method. The survival rates of F_0 and F_1nymphs, the longevity and fecundity of F_0 and F_1adults were investigated. The life-table of F_1 generation was constructed. The results showed that both sublethal doses could prolong the developmental duration and decrease the survival rate of F_0 nymphs. In addition, F_0 female adults treated by LC_（10） of thiamethoxam had significant longer lifespan compared to that of the control, and the fecundity of adults had no difference from that of the control. As for F_1 generation, both treatments significantly prolonged the developmental durations of nymphs. The oviposition amount of adults treated with LC_（10） of thiamethoxam was 22.24 eggs less than that of the control, while that of the adults treated with LC_（25） of thiamethoxam was significantly69.96 eggs less than that of the control. Both sublethal doses of thiamethoxam resulted in declining population trend index. The relative fitness of F_1 generation treated by LC_（10） and LC_（25）of thiamethoxam was reduced by 0.12 and 0.36, respectively. The results indicated that the sublethal dose of thiamethoxam had negative effect on S. furcifera.