几种杀虫剂对棉铃虫卵的防治效果试验

4种农药对棉铃虫Helicoverpaarmigera（hubner）卵进行了室内毒力测定及大田药效试验，结果表明，40％水胺硫磷、50％对硫磷对棉铃虫卵毒力较高，2000倍液田间喷雾药效分别为98.8％和99．0％；对棉铃虫初孵幼虫24小时防效分别为98．8％和98．2％；药效7天以上。防治费用较杀虫脒降低76.0％～78.4％，完全可以替代杀虫脒，适宜在陕西棉田推广应用。

The experiment of insecticides for the ova of Helicoverpa armigeta (Hubner)

The experiments of insecticidal toxicity were carried out in the laborary and field. The results showedtha the effectiveness of 40% Thimidan and 50% Folidol to the ova of cotton bollworms was 98.8% and 99.0%respectively, and to the neonatal larvae of cotton bollworms was 98.8% and 98.2% afer 24hs by spraying thetoxicant solution (2000 times) in the field. The effect can be lasted more than 7 dsys. The cost of insect pest control was reduced to 76.05% ～ 78.45% than that of Chlorodimeform. The two insecticides can be used instead ofChlorodimeform completely. As a result, both insecticides are sultabe to be extended for use in cotton fields inShahxi province.