噻嗪酮、烯啶虫胺及其复配制剂对褐飞虱3龄若虫的毒力测定

Toxicity Measure of Buprofezin, Nitenpyram and Their Mixtures to the Third Instar Nymphs of Brown Planthopper

在室内恒温条件下,采用稻苗浸渍法和稻茎浸渍法测定了噻嗪酮、烯啶虫胺及其复配制剂对褐飞虱3龄若虫的毒力,用孙云沛介绍的共毒系数法评价了不同剂型的噻嗪酮和烯啶虫胺复配制剂的联合作用。结果表明:噻嗪酮和烯啶虫胺质量比4∶1的悬浮剂,采用稻苗浸渍法测得其LC50值为1.68mg/L,共毒系数为191.53;采用稻茎浸渍法测得其LC50值为2.08mg/L,其共毒系数为203.38。噻嗪酮和烯啶虫胺质量比4∶1的二甲苯乳油,采用稻苗浸渍法测得其LC50值为1.80mg/L,共毒系数为178.76;采用稻茎浸渍法测得其LC50值为2.17mg/L,其共毒系数为194.94。当麻风树生物柴油作为2种药剂的复配制剂时,可提高混配制剂的增效作用,噻嗪酮和烯啶虫胺质量比4∶1的生物柴油乳油,采用稻苗浸渍法测得其LC50值为1.39mg/L,共毒系数为231.49;采用稻茎浸渍法测得其LC50值为1.57mg/L,其共毒系数为322.44。

Under the indoor temperature conditions, rice seedlings impregnation and rice stem impregnation methods were adopted to determine the toxicities of buprofezin, nitenpyram and their mixture to the third instar nymphs of brown planthoppers. The co-toxicity coefficient method introduced by Sun Yun-pei was adopted to evaluate the combined effects of the different mixtures of buprofezin and nitenpyram. The results of rice seedlings impregnation technique revealed an LC50 of 1.68 mg/L and CTC of 191.53 when buprofezin to nitenpyram mass ratio was kept at 4：1. On the other hand, with rice stem impregnation method, the corresponding values recorded for LC50 and CTC were 2.08 mg/L and 203.38 respectively. Furthermore, the LC50 and CTC were found to be 1.80 mg/L and 178.76 respectively with a mass ratio of 4：1 of xylene EC mixture of buprofezin and nitenpyrams by rice seedlings impregnation method. The LC50 and CTC values were however 2.17 mg/L and 194.94 respectively when measured with the help of rice stem impregnation technique. When Jatropha Bio-diesel was employed as an agent in the mixture of buprofezin and nitenpyram, the efficiency was enhanced significantly. This is evident from the figure that bio-diesel EC of buprofezin and nitenpyram with a mass ratio of 4：1 showed an LC50 of 1.39 mg/L and CTC of 231.49 when measured by rice seedlings impregnation method, whereas with rice stem impregnation method the corresponding value were 1.57 mg/L and 322.44 respectively.