几种杀虫剂对棉铃虫卵的防治效果试验

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

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 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.