嘧草醚对双季稻田杂草的防效及后茬作物的安全性影响

Effects of pyriminobac-methyl on weeds in double-cropping rice fields and safety to rice and following crops

为明确嘧草醚及其相关除草剂混用对移栽田杂草的防效及其对水稻和后茬作物的安全性,于2018年在江西双季稻田进行了田间试验。结果表明:10%嘧草醚WP对稗Echinochloa crus-galli有优异的防除效果,有效剂量45~120 g/hm^2处理药后45 d对早稻和晚稻田稗草的防效均在90%以上,且对水稻和后茬作物油菜、白菜、紫云英、小麦和马铃薯生长安全,但对阔叶类鸭舌草和莎草类异型莎草的防效较差;10%嘧草醚WP分别与10%苄嘧磺隆WP和25 g/L五氟磺草胺OD混用,对早稻和晚稻田稗草、鸭舌草和异型莎草的防效均达91%以上,且对水稻生长安全;而与扑草净混用对杂草的防效略低,且对水稻会产生药害,严重影响产量。因此,对于以稗草为优势种群的水稻田,可选用10%嘧草醚WP 45~60 g/hm^2进行防治;对于禾本科杂草、阔叶杂草和莎草科杂草发生并重的水稻田,可选择10%嘧草醚WP 30~45 g/hm^2与10%苄嘧磺隆WP或25 g/L五氟磺草胺OD 20~30 g/hm^2混用进行治理。

In order to clarify the efficacies of pyriminobac-methyl on weeds in double-cropping rice fields and its safety to rice and following crops,a field experiment was conducted in double-cropping rice fields in Jiangxi province in 2018.The results showed that pyriminobac-methyl 10%WP had good efficacy on Echinochloa crus-galli,which was over 90%in double-cropping rice fields at 45-120 g/hm^245 d after treatment.It was safe to rice and following crop,including rape,Chinese cabbage,Chinese milk vetch,wheat and potato growth,but the efficacy on broad-leaved weeds and Cyperaceae weeds was poor.The efficacies of mixed use of pyriminobac-methyl 10%WP with bensulfuron-methyl 10%WP and penoxsulam 25 g/L OD on Echinochloa crus-galli,Monochoria vaginalis and Cyperus difformis in early rice and late rice fields were more than 91%,and it was safe to the growth of rice.However,the efficacy of the mixture of pyriminobac-methyl 10%WP with prometryn 50%WP on weeds was low,and it also caused damage to rice growth,which seriously affected the rice yield.Therefore,pyriminobac-methyl 10%WP at 45-60 g/hm^2 can be used for controlling weeds in the rice field with Echinochloa crus-galli as the dominant population.The mixtures of pyriminobac-methyl 10%WP at 30-45 g/hm^2 with bensulfuron-methyl 10%WP or penoxsulam 25 g/L OD at 20-30 g/hm^2 can be used in rice fields with simultaneous occurrence of gramineae weeds,broad-leaved weeds and Cyperaceae weeds.