吡虫啉拌种量对小麦蚜虫的防治效果及其在小麦籽粒中的残留研究

Study on Control Effect and Safety of Seed Dressing with Imidacloprid against Wheat Aphid

不同小麦种植区、不同种植习惯以及不同播种期决定了小麦播种量差异较大。以小麦品种冀5265为试材,采用田间小区试验的方法,分别在小麦播种量为180、225和300 kg/hm2条件下,研究了吡虫啉不同拌种剂量对小麦出苗率、小麦蚜虫的防治效果以及小麦籽粒中残留的影响。结果表明:在3组播种量处理下,吡虫啉不同拌种剂量对小麦出苗率均没有影响;吡虫啉拌种防治小麦蚜虫具有较好的防治效果和较长的持效期,在整个麦蚜发生期无需施药。在小麦播种量相同的前提下,对小麦蚜虫的防治效果随拌种剂量的提高而上升,持效期延长;在拌种剂量相同的前提下,随着播种量的加大,前中期防效无显著差异,后期防效提高,持效期延长。在试验剂量下,小麦籽粒中吡虫啉残留量均低于美国规定的小麦籽粒中吡虫啉的最高限量标准,不同的播种量对小麦籽粒中吡虫啉残留量没有显著影响。吡虫啉拌种防治麦蚜技术在试验剂量下对作物安全,可高效控制麦蚜为害,在产品中残留也低于国际最高限量标准。

Different growing areas,different planting habits and different sowing date resulted in the large differences of wheat seed sowing quantity,which could have great influence on the control effect and safety of seed dressing with imidacloprid against wheat aphid.Using wheat variety Ji5265 as the material,the control effect and safety of seed dressing with imidacloprid against wheat aphid were studied.The results showed that under different sowing rate,the dose of imidacloprid had no influence on the emergence rate.Seed dressing with imidacloprid had excellent control efficacy and long persistent period to wheat aphids,which could dispense with other pesticides to control the insect.Under the same sowing rate,the control effect was improved with the increasing of the dose of imidacloprid,and the persistent period was prolonged.Under the same dose of imidacloprid,with the increasing of sowing rate,the control effect had no significant difference at earlier and middle stage,and it was improved and the persistent period was prolonged at later stage.The residue of imidacloprid in kernel was lower than the highest limited standards in USA.The sowing rate had no significant influence on residue of imidacloprid in kernel.Seed dressing with imidacloprid was safe to crops,had good control efficacy on wheat aphids,and remained lower residues in products.