九种除草剂对玉米田杂草的防除效果及其安全性评价

Control efficacies of nine herbicides to weeds and their safety evaluation in maize fields

为明确9种常用除草剂对玉米田杂草的防除效果及其安全性。在福建省甜玉米制种田,采用茎叶喷雾法开展了9种除草剂在推荐剂量下的田间药效试验,并测定了除草剂对甜玉米及其后茬花椰菜和萝卜的安全性。结果表明,施药后25 d,9种除草剂的杂草株防效和鲜重防效均在92%以上;施药后50 d,27%烟·硝·莠去津可分散油悬浮剂[有效成分(下同)810 g/hm^2]和25%硝磺·莠去津可分散油悬浮剂(750 g/hm^2)处理的杂草防除效果最好,以20%氯氟吡氧乙酸乳油(180 g/hm^2)处理的杂草防除效果最差,杂草覆盖表现为重度。供试的9种除草剂对甜玉米生长安全,无明显药害症状,且部分药剂有明显的增产效果,其中以25%硝磺·莠去津可分散油悬浮剂、20%烟嘧·辛酰溴苯腈可分散油悬浮剂(300 g/hm^2)、80%莠去津可湿性粉剂(1440 g/hm^2)和27%烟·硝·莠去津可分散油悬浮剂处理的玉米产量较高,与对照相比,增产率分别为21.03%、19.26%、18.74%和16.84%。10%硝磺草酮悬浮剂(150 g/hm^2)、27%烟·硝·莠去津可分散油悬浮剂、33.5%硝磺·异丙草胺·莠去津悬浮剂(1005 g/hm^2)和30%苯唑草酮悬浮剂(27 g/h m^2)处理对后茬花椰菜和萝卜均有较好的增产效果,增产率分别为18.05%和13.68%、3.37%和12.67%、15.45%和11.06%、8.21%和11.67%,但40 g/L烟嘧磺隆可分散油悬浮剂(60 g/hm^2)对后茬花椰菜和萝卜的生长有抑制作用,与清水对照相比,分别减产9.74%和3.57%。研究结果可为甜玉米田杂草防除有效药剂的合理选择和应用提供科学依据。

In this study,the control efficacies of nine herbicides against weeds were investigated and their safety in the maize field was evaluated.The efficiencies of nine herbicides at the recommended dosages were carried out using the method of spraying stem and leaves in seed production field for sweet maize.Their risk to sweet maize and post-harvest vegetables(cauliflower and radish)was also studied in the experimental field.The results showed that the control efficiencies of nine herbicides on weed and fresh weight were all above 92%at 25 days after the application.The prevention efficacies of 27%nicosulfuron+mesotrione+atrazine OD(810 g a.i./hm^2)and 25%mesotrione+atrazine OD(750 g a.i./hm^2)were the best ones.And that of 20%fluroxypyr EC(180 g a.i./hm^2)was the lowest one,which showed high degree weed coverage after 50 days.In addition,the tested herbicides were safe and had no negative influence on the growth of sweet maize,and some herbicides could even significantly increase the production.The yield of maize after the treatment by 25%mesotrione+atrazine OD,20%nicosulfuron+bromoxynil octanoate OD(300 g a.i./hm^2),80%atrazine WP(1440 g a.i./hm^2)and 27%nicosulfuron+mesotrione+atrazine OD was higher than that treated by other herbicides.Compared with the control,the yields were increased by 21.03%,19.26%,18.74%and 16.84%,respectively.Meanwhile,the treatments of 10%mesotrione SC(150 g a.i./hm^2),27%nicosulfuron+mesotrione+atrazine OD,33.5%mesotrione+propisochlor+atrazine SC(1005 g a.i./hm^2)and 30%topramezone SC(27 g a.i./hm^2)could improve the yield of the post-harvest cauliflower and radish.The increasing rates of yields were 18.05%and 13.68%,3.37%and 12.67%,15.45%and 11.06%,and 8.21%and 11.67%,respectively.While the 40 g/L nicosulfuron OD(60 g a.i./hm^2)had a negative effect on the yield of cauliflower and radish.The yields were decreased by 9.74%and 3.57%compared with the control.The results could provide scientific basis on selecting and applying effective herbicides to control weeds in sweet corn field.