吡虫啉包衣对黄瓜瓜蚜的防治效果及包衣后药剂在植株体内的分布

为探讨吡虫啉包衣对黄瓜瓜蚜的防治效果及包衣后吡虫啉在黄瓜植株体内的分布动态,以不同剂量的40%吡虫啉悬浮种衣剂包衣处理黄瓜种子,并测定了不同时间内其对瓜蚜Aphis gossypii Glover的防治效果,同时使用HPLC检测了瓜苗出土后不同时期吡虫啉在黄瓜植株各部位的分布量。结果表明,100 kg黄瓜种子用吡虫啉(有效成分)240 g、480 g和960 g的处理在瓜苗出土35 d后,瓜苗上所接瓜蚜的校正虫口减退率仍分别达到89.2%、92.0%和97.7%。经过吡虫啉包衣处理后的黄瓜种子在出苗后 3~14 d内,植株体内的吡虫啉含量逐渐增加,14 d时达到峰值后逐渐减少; 黄瓜植株不同地上部位中吡虫啉的含量不均匀,其中下部叶片药剂含量最高,其次是上部叶片,茎部最低。

Effect of Cucumber Seed Coating with Imidacloprid against Aphis gossypii and the Pesticide's Distribution in the Plant

Control efficacy of cucumber seed coating with 40% imidacloprid FS against Aphis gossypii Glover was tested. The results showed that 35 d after treating the seed with imidacloprid (a.i) by 240 g, 480 g and 960 g per 100 kg seed,the decline rates of A.gossypii were still 89.2%,92.0% and 97.7%,respectively. Simultaneously the distribution of imidacloprid in the cucumber plant was tested by HPLC. The results revealed that the content of imidacloprid in cucumber plant kept increasing from 3 to 14 d after the plant emergence,and then decreased slowly. The content of imidacloprid in the lower leaf was the highest,in the top leaf was moderate and in the stem was the lowest.