三叶斑潜蝇的防治技术研究

Techniques for controlling Liriomyza trifolii

【目的】三叶斑潜蝇Liriomyza trifolii是一种世界性农业害虫,主要危害蔬菜和花卉,在全国的危害范围不断扩大,目前是江苏地区斑潜蝇的优势种。通过开展药剂筛选和农业防治技术的联合应用,能减少农业生产中的农药使用,达到安全有效地控制三叶斑潜蝇危害的目的。【方法】本研究选用高效氯氰菊酯、杀虫双、阿维·苏云菌、灭蝇胺、斑潜净5种药剂对三叶斑潜蝇开展田间和室内药效试验;同时研究了覆土和浸水对三叶斑潜蝇的控制效果。【结果】田间三叶斑潜蝇幼虫防治试验表明,杀虫双效果较好、见效快,但对寄生蜂的影响较大;斑潜净、阿维·苏云菌和灭蝇胺的防效较低,但对寄生蜂较为安全;高效氯氰菊酯几乎没有防效。室内药效试验表明,杀虫双和斑潜净对三叶斑潜蝇的幼虫药效较高,持效期长;而灭蝇胺虽然对幼虫没有直接防效,但处理后的幼虫所化蛹均不能羽化,对下一代的种群增长具有很好的控制作用;高效氯氰菊酯和阿维·苏云菌的药效较差;试验所用药剂对三叶斑潜蝇的蛹均无效果。此外,三叶斑潜蝇1日龄蛹在浸水3-4d失去羽化能力;覆土深度达到5cm时,其羽化率降低到20%以下,对羽化抑制效果明显。【结论】化学农药在田间和室内的防治药效差异较大,因此确定农药的防效需要进行多种条件下的田间试验。在药剂防治三叶斑潜蝇时,尽量选用高效、低毒的化学农药在低龄幼虫期使用,注意保护天敌。本文推荐种植者在田间实际中将化学与非化学防治措施结合使用,即在灌水3-4 d或深耕5 cm的基础上,在三叶斑潜蝇幼虫时期使用杀虫双和斑潜净能够有效地控制三叶斑潜蝇的发生危害。

[Objectives]Liriomyza trifolii(Burgess)is an important global pest of vegetables and other horticultural plants that has recently become the dominant leaf miner in Jiangsu and is spreading rapidly throughout China.Choosing the correct pesticide,in combination with soil management techniques,can effectively control this pest with minimal pesticide use.[Methods]The effectiveness of five insecticides for controlling L.trifolii;beta-cypermethrin,bisultap,abamectin+Bacillus thuringiensis(abamectin+B.t.),cyromazine and a 20%mixture of abamectin+monosultap,was evaluated in the field and laboratory.The effects of deep ploughing and intensive irrigation on L.trifolii was also evaluated.[Results]Bisultap was the most effective insecticide for in controlling L.trifolii larvae in the field but it had the disadvantage of having an adverse impact on parasitoids.Although abamectin+B.t.,cyromazine and the 20%mixture of abamectin+monosultap,were less effective than bisultap in the field,they were safe to parasitoids whereas Beta-cypermethrin had no significant effect on L.trifolii larvae.In laboratory experiments,bisultap and the 20%mixture of abamectin+monosultap effectively controlled L.trifolii larvae over a long period.Although cyromazine had no detectable effect on larvae,the pupae of larvae treated with it failed to emerge,indicating that this insecticide can effectively control the next generation.In addition,one-day-old pupae of L.trifolii failed to emerge after being soaked in water for 3-4 days and the eclosion rate decreased to less than 20%when soil was covered to a depth of 5 cm.[Conclusion]The efficacy of pesticides in the field and laboratory were quite different,highlighting the necessity of conducting field experiments under various conditions to determine pesticide effectiveness.Effective pesticides that are the least toxic to natural enemies should be selected and applied during the larval stage to control L.trifolii in the field.We recommend that growers combine chemical and non-chemical control measures.Application of bisultap and a 20%mixture of abamectin+monosultap during the larval stage,combined with deep ploughing up to 5 cm and 3-4 days of irrigation,can effectively control L.trifolii in the field.