防治水稻白背飞虱高毒农药替代药剂的室内筛选及对吡虫啉的抗性风险评估

 为筛选高毒农药的替代药剂，采用稻茎浸渍法测定了7类共21种杀虫剂对2006年和2007年采自南京市江浦地区的白背飞虱种群3龄若虫的毒力。结果表明,噻虫嗪、吡虫啉、噻嗪酮对白背飞虱3龄若虫的毒力最高(LC50=004~026 mg/L)；烯啶虫胺、丁烯氟虫腈、吡蚜酮、啶虫咪、氯噻啉、毒死蜱、氟虫腈等也有较高的毒力(LC50＜4.50 mg/L）；异丙威、敌敌畏虽然触杀毒力稍低(LC50＞19.85 mg/L)，但两者在生产上仍广泛应用，所以把以上12种药剂作为田间药效试验的推荐品种；同时还比较了该地区白背飞虱种群对供试药剂敏感性的年度间差异，其中对毒死蜱、异丙威、丁硫克百威、速灭威这4种药剂的敏感性下降了66.7%~71.4%。对2006年南京江浦种群用吡虫啉连续筛选15代的结果表明，1~15代抗性上升433倍，抗性现实遗传力为0.2295，存在抗性风险。另外，还讨论了白背飞虱的综合防治。

Laboratory Screening of Alternatives to Highly-Toxic Insecticides for Controlling the White-Backed Planthopper, Sogatella furcifera and Resistance Risk Assessment to Imidacloprid in Rice

To screen alternative insecticides for controlling the white backed planthopper, Sogatella furcifera (Horváth), toxicities of 21 insecticides fallen into seven categories against the third instar nymphs of Sogatella furcifera, which were collected from Jiangpu District, Nanjing, China were evaluated by the rice stem dipping method in 2006 and 2007. The results indicated that thiamethoxam, buprofezin and imidacloprid had the highest toxicities (LC50=0.04-0.26 mg/L); nitenpyram, butylene fipronil, pymetrozine, acetamiprid, imidaclothiz, chlorpyrifos and fipronil showed good efficacy (LC50＜4.50 mg/L), suggesting that the above insecticides were potential alternatives to highly toxic insecticides for field trials. Although isoprocarb and dichlorvos showed less efficacy (LC50＞19.85 mg/L), these two insecticides were also recommended as the alternatives because they are being applied widely in practice. According to the year to year variation in susceptibility of Sogatella furcifera to the insecticides between 2006 and 2007， it was noted that the susceptibilities to chlorpyrifos, isoprocarb, carbosulfan, metolcarb were significantly reduced, with the reducing rate of 2.0 to 2.5 fold. With continuous selection with imidacloprid for 15 generations, the LC50 of the population collected from Jiangpu in 2006 increased by 4.33 fold and its realized heritability (h2) was 0.2295. In addition, integrated management strategies for the white backed planthopper were also proposed.