Rocha Luiz C D, Carvalho Geraldo A, Moura Alexandre P, Cosme Luciano V, Vilela Fabrícia Z
Depto. Entomologia, Univ. Federal de Lavras, C. postal 3037, 37200-000, Lavras, MG.
Neotrop Entomol. 2006 Jan-Feb;35(1):83-92. doi: 10.1590/s1519-566x2006000100012.
The objective of this study was to evaluate the toxicity of some pesticides used in chrysanthemum crops to eggs and nymphs of Orius insidiosus (Say). The bioassays were carried out at 25 +/- 2 degrees C, 70 +/- 10% RH and 12h photophase. For the tests with eggs, stems of Bidens pilosa L. previously exposed to predator oviposition were dipped for five seconds in aqueous dilution of the pesticides, using 40 eggs per treatment. The pesticides were applied on nymphs using a Potter's tower. Forty first-instar and twenty second-instar nymphs of O. insidiosus were used per treatment in the tests with nymphs. The adults from eggs and nymphs treated were grouped in couples to study the pesticides effects on its reproductive parameters. None tested pesticide affected the viability of treated eggs. Azoxystrobin, benomyl, imibenconazole, iprodione, metalaxyl + mancozeb and triforine were harmless to first- and second-instar nymphs of O. insidiosus, whereas abamectin, acephate and chlorfenapyr were shown to be harmful to nymphs of both first and second instars. The pre-oviposition period, the daily number of eggs, number of eggs in ten days, and egg viability were not affected by azoxystrobin, benomyl, imibenconazole, iprodione, metalaxyl + mancozeb and triforine. These pesticides, for showing low toxicity to the predator, can be recommended in disease management programs for chrysanthemum crops, in association with O. insidiosus.
本研究的目的是评估用于菊花作物的某些农药对暗黑赤眼蜂（Say）卵和若虫的毒性。生物测定在25±2℃、70±10%相对湿度和12小时光照期下进行。对于卵的试验，将先前暴露于捕食者产卵的三叶鬼针草茎在农药的水稀释液中浸泡5秒钟，每个处理使用40枚卵。使用波特喷雾塔将农药施用于若虫。在若虫试验中，每个处理使用40只暗黑赤眼蜂一龄若虫和20只二龄若虫。将经处理的卵和若虫羽化出的成虫配对分组，以研究农药对其生殖参数的影响。没有一种测试农药影响处理后卵的活力。嘧菌酯、苯菌灵、亚胺唑、异菌脲、甲霜灵+代森锰锌和嗪氨灵对暗黑赤眼蜂一龄和二龄若虫无害，而阿维菌素、乙酰甲胺磷和溴虫腈对一龄和二龄若虫均有害。嘧菌酯、苯菌灵、亚胺唑、异菌脲、甲霜灵+代森锰锌和嗪氨灵对产卵前期、每日产卵数、十天内产卵数和卵活力没有影响。由于这些农药对捕食者显示出低毒性，因此在与暗黑赤眼蜂联合使用的菊花作物病害管理计划中可以推荐使用。
