不同施药方式下噻虫嗪和噻虫胺对韭菜迟眼蕈蚊的防治效果

为提高田间韭菜养根期噻虫嗪和噻虫胺对韭菜迟眼蕈蚊的防治效果,通过喷淋和灌溉施药方式研究了噻虫嗪和噻虫胺在土壤中的分布情况、喷淋施药后在田间的移动性以及对韭蛆的防治效果和对韭菜生长指标的影响。结果表明,喷淋施药比灌溉施药利于药液到达地下靶标位置,且药剂浓度随着土壤深度增加而减小;喷淋施药后药剂在韭菜根部土壤中的浓度明显高于其在行间土壤中的浓度;施药后120 d与7 d相比,药剂在垂直方向上出现下移,在水平方向上随水流方向移动;12 kg(a.i.)/hm2噻虫嗪和3、6 kg(a.i.)/hm2噻虫胺喷淋施药后对韭菜迟眼蕈蚊的防治效果在80%以上,且均可维持120 d以上,并对韭菜生长有促进作用。因此,利用噻虫嗪和噻虫胺喷淋施药防治韭菜养根期的韭菜迟眼蕈蚊是可行的。

Control effects of thiamethoxam and clothianidin against Bradysia odoriphaga with different application methods

To improve the control effect of thiamethoxam and clothianidin against Bradysia odoriphaga in the field, their distribution in soil, movement characteristics in the field, control effect against B. odoriphaga and impact on the growth index of Chinese chive were studied by using drip washing and chemigation methods. The results showed that the drip washing method was easier to reach the target than chemigation method. The concentration of insecticide in the soil decreased with the increase of soil depth, and the concentration in the rhizosphere soil was higher than that in the inter-row soil of Chinese chive. Compared to the distribution at the 7th day after application, insecticide moved much deeper and wider at the 120th day after application. The control effects of 12 kg (a.i.)/hm² thiamethoxam and 3, 6 kg (a.i.)/hm² clothianidin were over 80%, lasting at least 120 days and promoting the growth of Chinese chive. Therefore, thiamethoxam and clothianidin could be used to control B. odoriphaga in the root-rearing period of Chinese chive by the drip washing method.