杀虫剂使用失当是甜菜夜蛾大发生的重要原因

Inseeticide abuse is an important cause of beet armyworm outbreak

近年来,甜菜夜蛾Spodoptera exigua(H櫣bner)在我国的危害面积越来越广,造成的损失越来越大。为了更好地了解甜菜夜蛾的发生和成灾规律,改善和提高预测与防治技术,文章就杀虫剂对甜菜夜蛾及其天敌的影响进行了分析。结果表明,杀虫剂使用失当是甜菜夜蛾大发生的重要原因。甜菜夜蛾对杀虫剂的抗药性水平超过天敌,而天敌的飞行、搜索、攻击和产卵等行为,以及生长、发育、生殖和寿命等又容易受杀虫剂的干扰,产生负面影响,从而降低天敌对甜菜夜蛾的控制能力。因此,如何合理使用杀虫剂,在有效控制甜菜夜蛾种群的同时,达到保护天敌的目的,将是我们面临的新课题。

The improper application of insecticide is one of the most important causes for the resurgence of beet armyworm, Spodoptera exigua （HUbner）. The insecticides have double effects. On the one hand, it reduces the population density of pest temporarily, and increases the insecticide resistance. On the other hand, its side-effects on natural enemies are negative which could destroy the balance of pest-natural enemies system, and provides the opportunity for the beet armyworm to escape natural controls. Insecticides could influence behavior of natural enemies including mating, foraging and so on. Some insecticides also disturb emergence, longevity, fecundity, and prolong the developmental period, in natural enemies. It＇ s very important to consider cautiously that how to use insecticides in the right way. In order to protect natural enemies, insecticides should be used safely without affecting natural enemies. Only if insecticides were used properly in field, that can bring the IPM program into effect.