【摘要】 <正> 棉蚜的药剂防治,自从用六六六及E605替代了棉油皂及棉油乳剂之后,已经可以说基本上获得了解决。这两种药剂对棉蚜的毒性都极高;在适当的剂量及喷洒时,可以得到极好的防治效果。主要的关键,在施用这两种药剂时的适当时期和次数。由於这两种药的残效时间都比较短,因此,过了一定时期后,就必须再行喷洒。不能适期的防治,常会增加喷洒的次数;若能掌握虫情,在害虫发生关键时期加以防治,就可以在全年中只喷洒3次,害虫基本上可被抑制。更多还原

【Abstract】 The following organc-phosphorus insecticides were used in the present experiment for thecontrol of cotton aphids, Aphis gossypii Glover: Systox (E-1059), Metasystox (4404), OMPA,EPN-300, and E-605 (Parathion). The treatment of these insecticides included: spraying ofplants, smoking of seeds, and soil application. The systemic action of Systox, Matasystox, and OMPA was verified; E-605 showedvery little systemic action.The toxicity of these insecticides follows the order: E-605>Systox>Metasystox=OMPA>EPNbut the residual action of these insecticides follows the order: Systox>Metasystox=OMPA>E-605=EPN. Both toxieity and residual action varied with the treatments. Thus toxicity was. greatest. inspraying experiments, but residual action showed the longest duration. in soil-application expe-riments. Both Systox and Metasystox showed phytotoxicity at concentrations from 0.5 to 1.0%,especially to potted plants; however, OMPA was safe even in 1.0% concentration.0.3% Systox and Metasystox may protect young cotton scedlings. from cotton aphids for10 to 19 days. The results of the present experiments were compared with those of previous workers.inthis country (Wen, 1954, Chang, 1955),the differences in these results were. discussed. Theperspectives of the use of these new systemic insecticides in the practieal control of cottonaphids were also discussed.更多还原