【摘要】 用四种不同浓度烟草浸出液防治菜青虫 ,与 4 0 %乐果比较 ,试验结果表明 2倍液防治效果最好 ,杀虫率平均达 87.5 %。以清水为对照 ,采用间接萃取比色法 ,做出烟碱的标准工作曲线。喷药 2 4、4 8、72h后采集样品 ,测定其残留 ,4种浓度的残留均未检出。同时进行蔬菜生理指数的测定 ,结果显示喷药后叶绿素的含量显著增多 ,维生素C含量变化明显。更多还原

【Abstract】 A research was conducted to prevent and kill Cabbage Caterpillar with four different concentrations of Tobacco extract .Compared with the 40 percent of Rogor,The experiment showed the preventive and killing effect was perfect when using two times of the original extract,up to 87.5%.In contrast to pure water,the standardized curve of nicotine samples was made by the method of colorimetry .24hours?48hours?72hours,respectively after spraying,collecting the samples to measure their residue,the results indicated that none of the four different concentrations was checked out.In addition,the measurement of the vegetable Physiological index showed that the content of chlorophyll increased significantly and the variation of Vitamin C was of significance .更多还原