Department of Agricultural Entomology, Tamilnadu Agricultural University, India.
Chemosphere. 2010 Jul;80(5):498-503. doi: 10.1016/j.chemosphere.2010.04.070. Epub 2010 May 26.
The green miridbug, Cyrtorhinus lividipennis, an important natural enemy of the rice brown planthopper (BPH), Nilaparvata lugens plays a major role as a predator in suppressing the pest population. The study assessed the impact of certain potential insecticides used in the rice ecosystem on the miridbug predator and brown planthopper through contact toxicity. Eleven insecticides, including neonicotinoids, diamides, azomethine pyridines, carbamates, pyrethroids, organophosphates and cyclodienes were selected to test their toxicities against the nymphs of C. lividipennis and N. lugens. Median lethal concentration (LC(50)) was determined for each insecticide using an insecticide-coated vial (scintillation) residue bioassay, which revealed BPMC as the highly toxic chemical with an LC(50) of 0.003mga.iL(-1) followed by ethofenprox and clothianidin with LC(50) of 0.006mga.iL(-1) at 48 HAT against C. lividipennis and ethofenprox as the highly toxic chemical with an LC(50) of 0.009mga.iL(-1) followed by clothianidin with an LC(50) of 0.211mga.iL(-1) at 48h after treatment (HAT) against N. lugens. Among the insecticides tested, the cyclodiene compound, endosulfan had the lowest acute contact toxicity (LC(50)=66.65mga.iL(-1) at 48 HAT) to C. lividipennis. Among the insecticides tested, endosulfan, chlorpyriphos, acephate and methyl parathion are regarded as safer to C. lividipennis based on selectivity ratio, hazard quotient and probit substitution method of risk assessments.
绿盲蝽，作为稻褐飞虱（Nilaparvata lugens）的重要天敌，在捕食稻褐飞虱种群方面发挥了重要作用。本研究通过接触毒性评估了某些在水稻生态系统中使用的潜在杀虫剂对捕食性绿盲蝽和稻褐飞虱的影响。选择了 11 种杀虫剂，包括新烟碱类、二酰胺类、脒基吡啶类、氨基甲酸酯类、拟除虫菊酯类、有机磷类和环戊二烯类，以测试它们对 C. lividipennis 和 N. lugens 若虫的毒性。使用杀虫剂包被管（闪烁）残留生物测定法确定每种杀虫剂的半致死浓度（LC50），结果表明 BPMC 是高毒化学物质，其 LC50 为 0.003mg a.i.L（-1），其次是乙虫腈和噻虫嗪，LC50 分别为 0.006mg a.i.L（-1），在 48 小时接触时间（HAT）时对 C. lividipennis 有效，乙虫腈是高毒化学物质，其 LC50 为 0.009mg a.i.L（-1），其次是噻虫嗪，其 LC50 为 0.211mg a.i.L（-1），在 48 小时接触时间（HAT）时对 N. lugens 有效。在所测试的杀虫剂中，环戊二烯化合物硫丹对 C. lividipennis 的急性接触毒性最低（LC50=66.65mg a.i.L（-1），在 48 小时接触时间（HAT））。在所测试的杀虫剂中，根据选择性比、危害商和风险评估的概率替代法，硫丹、毒死蜱、乙酰甲胺磷和马拉硫磷被认为对 C. lividipennis 更安全。
