Musser Fred R, Shelton Anthony M
Department of Entomology, Cornell University, New York State Agricultural Experiment Station, Geneva, New York 14456, USA.
J Econ Entomol. 2003 Feb;96(1):71-80. doi: 10.1603/0022-0493-96.1.71.
Sweet corn, Zea mays L., is attacked by a variety of insect pests that can cause severe losses to the producer. Current control practices are largely limited to the application of broad-spectrum insecticides that can have a substantial and deleterious impact on the natural enemy complex. Predators have been shown to provide partial control of sweet corn pests when not killed by broad-spectrum insecticides. New products that specifically target the pest species, while being relatively benign to other insects, could provide more integrated control. In field trials we found that transgenic Bt sweet corn, and the foliar insecticides indoxacarb and spinosad are all less toxic to the most abundant predators in sweet corn (Coleomegilla maculate [DeGeer], Harmonia axyridis [Pallas], and Orius insidiosus [Sav]) than the pyrethroid lambda cyhalothrin. Indoxacarb, however, was moderately toxic to coccinellids and spinosad and indoxacarb were somewhat toxic to O. insidiosus nymphs at field rates. Bt sweet corn and spinosad were able to provide control of the lepidopteran pests better than or equal to lambda cyhalothrin. The choice of insecticide material made a significant impact on survival of the pests and predators, while the frequency of application mainly affected the pests and the rate applied had little effect on either pests or predators. These results demonstrate that some of the new products available in sweet corn allow a truly integrated biological and chemical pest control program in sweet corn, making future advances in conservation, augmentation and classical biological control more feasible.
甜玉米（Zea mays L.）受到多种害虫的侵袭，这些害虫会给生产者造成严重损失。目前的防治措施主要局限于使用广谱杀虫剂，而这可能会对天敌群落产生重大的有害影响。研究表明，在未被广谱杀虫剂杀死的情况下，捕食性天敌能够对甜玉米害虫起到部分控制作用。专门针对害虫种类、同时对其他昆虫相对无害的新产品，可能会提供更综合的防治方法。在田间试验中，我们发现转基因Bt甜玉米、以及叶面杀虫剂茚虫威和多杀菌素，对甜玉米中最常见的捕食性天敌（黄斑大蚊[DeGeer]、异色瓢虫[Pallas]和暗黑赤眼蜂[Sav]）的毒性都低于拟除虫菊酯高效氯氟氰菊酯。然而，茚虫威对瓢虫具有中等毒性，多杀菌素和茚虫威在田间使用剂量下对暗黑赤眼蜂若虫有一定毒性。Bt甜玉米和多杀菌素对鳞翅目害虫的防治效果优于或等同于高效氯氟氰菊酯。杀虫剂的选择对害虫和捕食性天敌的存活有显著影响，而施药频率主要影响害虫，施药剂量对害虫和捕食性天敌的影响都很小。这些结果表明，甜玉米中现有的一些新产品能够实现真正的生物与化学害虫综合防治方案，使未来在保护、增殖和经典生物防治方面取得更大进展变得更加可行。
