Galvan T L, Koch R L, Hutchison W D
Department of Entomology, 219 Hodson Hall, 1980 Folwell Avenue, University of Minnesota, St. Paul, MN 55108, USA.
J Econ Entomol. 2005 Jun;98(3):780-9. doi: 10.1603/0022-0493-98.3.780.
Use of insecticides with low toxicity to natural enemies is an important component of conservation biological control. In this study, we evaluated the toxicity of insecticides used in sweet corn, Zea mays L., and soybean, Glycine max (L.) Merr., to the multicolored Asian lady beetle, Harmonia axyridis (Pallas), under laboratory and field conditions. Field experiments conducted in sweet corn in 2003 and 2004 and in soybean in 2003, showed that H. axyridis was the most abundant predator. In sweet corn, densities of H. axyridis larvae in plots treated with spinosad or indoxacarb were generally higher than in plots treated with chlorpyrifos, carbaryl, bifenthrin, and A-cyhalothrin. In soybean, densities of H. axyridis larvae in plots treated with chlorpyrifos were higher than in plots treated with lambda-cyhalothrin. Laboratory experiments were conducted to evaluate the acute toxicity of insecticides to eggs, first and third instars, pupae, and adults. Spinosad, followed by indoxacarb, were the least toxic insecticides for all life stages of H. axyridis. Conventional insecticides showed high toxicity to H. axyridis when applied at field rates under laboratory conditions. Overall, first instars were most susceptible to the insecticides tested, followed by third instars and adults, eggs, and pupae. Our results suggest that spinosad, and to a lesser extent indoxacarb, offer reduced toxicity to H. axyridis and would be beneficial for conservation biological control in agricultural systems where H. axyridis is abundant.
使用对天敌毒性低的杀虫剂是保护型生物防治的一个重要组成部分。在本研究中，我们在实验室和田间条件下评估了用于甜玉米（Zea mays L.）和大豆（Glycine max (L.) Merr.）的杀虫剂对多异瓢虫（Harmonia axyridis (Pallas)）的毒性。2003年和2004年在甜玉米以及2003年在大豆上进行的田间试验表明，多异瓢虫是最丰富的捕食性天敌。在甜玉米中，用多杀菌素或茚虫威处理的地块中多异瓢虫幼虫的密度通常高于用毒死蜱、西维因、联苯菊酯和高效氯氟氰菊酯处理的地块。在大豆中，用毒死蜱处理的地块中多异瓢虫幼虫的密度高于用高效氯氟氰菊酯处理的地块。进行实验室试验以评估杀虫剂对卵、一龄和三龄幼虫、蛹及成虫的急性毒性。多杀菌素，其次是茚虫威，对多异瓢虫的所有生命阶段毒性最低。在实验室条件下按田间用量施用时，传统杀虫剂对多异瓢虫显示出高毒性。总体而言，一龄幼虫对所测试的杀虫剂最敏感，其次是三龄幼虫、成虫、卵和蛹。我们的结果表明，多杀菌素以及在较小程度上的茚虫威，对多异瓢虫的毒性较低，在多异瓢虫数量丰富的农业系统中，这将有利于保护型生物防治。
