双唑草腈对双季水稻田杂草的防效及后茬作物的影响

通过大田试验测定了双唑草腈及其与苄嘧磺隆、五氟磺草胺和扑草净混用对双季水稻田杂草的防效,并评价了双唑草腈对水稻及后茬作物的安全性。结果表明:2%双唑草腈GR对双季水稻田杂草具有良好的防治效果,210、315和420 g/hm~2处理药后30、45 d对禾本科杂草和阔叶类杂草的防效均在87%以上,低剂量140 g/hm~2处理药后30、45 d对双季水稻田禾本科杂草和阔叶类杂草防效均在75%以上。2%双唑草腈GR 140、210、315和420 g/hm~2处理对后茬作物小白菜、马铃薯、小麦、紫云英和冬季油菜生长安全。2%双唑草腈GR以140、210 g/hm~2分别与苄嘧磺隆或五氟磺草胺混用,药后30、45 d对禾本科杂草和阔叶杂草的防效均在93%以上,显著优于2%双唑草腈GR相应浓度的单剂处理,其中2%双唑草腈GR 210 g/hm~2+10%苄嘧磺隆WP 30 g/hm~2混用可以达到2%双唑草腈GR 315 g/hm~2处理的防治效果,且对水稻生长安全;单独施用50%扑草净WP 450 g/hm~2对双季稻田禾本科杂草的防效较差,其与2%双唑草腈GR混用后防效显著提高,但对水稻生长有较强的抑制作用。综上,双唑草腈及其与苄嘧磺隆、五氟磺草胺混用对双季水稻安全,可在双季水稻田推广应用。

Efficacy of pyraclonil on weeds in double season rice fields and the effects on following crops

The efficacies of pyraclonil 2% GR and its mixture with bensulfuron methyl, penoxsulam and prometryn on weeds in the fields of double season rice were tested, and the safety of pyraclonil on rice and following crops were evaluated. The results showed that pyraclonil 2% GR has a good control effect on weeds in double season rice fields, with the efficacies above 87% at the dosage of 210, 315, and 420 g/hm 2 30 and 45 days post treatment. The treatment with low dose of 140 g/hm 2 had more than 75% control effects on grass weeds and broad leaved weeds 30 and 45 days later. The treatments with pyraclonil 2% GR 140, 210, 315 and 420 g/hm 2 were safe for the growth of following crops, including pakchoi, potato, wheat, milk vetch and winter rape. The mixtures of 140 g/hm 2 and 210 g/hm 2 pyraclonil 2% GR with bensulfuron methyl or penoxsulam showed an efficacy of above 93% against grass weeds and broad leaved weeds 30 and 45 days post treatment, which were significantly better than that of pyraclonil 2% GR treated alone at 140 g/hm 2, 210 g/hm 2. In addition, pyraclonil 2% GR 210 g/hm 2 + bensulfuron methyl 10% WP 30 g/hm 2 can achieve the effect of pyraclonil 2% GR 315 g/hm 2, and it is safe for rice growth. The application of prometryn 50% WP 450 g/hm 2 alone had a poor control effect on the grass weeds in the double cropping paddy field. The control effect of prometryn 50% WP was significantly improved when mixed with pyraclonil 2% GR, but showed a strong inhibitory effect on rice growth. Therefore, pyraclonil and its mixture with both bensulfuron methyl and penoxsulam have an excellent application prospect in the field of double season rice.