三氟啶磺隆与精喹禾灵混用的联合除草作用及其对棉花的安全性研究

为明确三氟啶磺隆与精喹禾灵混用的联合除草作用及其对棉花的安全性,采用温室盆栽生物测定法,测定了其对香附子、马唐、牛筋草、马齿苋和反枝苋的联合除草作用,并对不同品种棉花的安全性及其在棉花与杂草之间的选择系数进行了研究。结果显示:三氟啶磺隆与精喹禾灵混用对香附子、马齿苋的防除效果为加成或增效作用,对马唐、牛筋草和反枝苋则以加成作用为主。当m(三氟啶磺隆)∶m(精喹禾灵)=1∶3和1∶4时,有效成分80 g/hm2的处理对供试棉花品种均安全,而有效成分160 g/hm2处理则对不同棉花安全性差异较大,其中对山农棉8号鲜重的抑制率较高,对鲁棉研36号则较安全;两者复配剂在棉花与杂草间的选择系数明显高于三氟啶磺隆单剂,提高了三氟啶磺隆对棉花的安全性。

Weed control efficacy and safety evaluation to cotton of combinations of trifloxysulfuron and quizalofop-p-ethyl

Whole-plant dose response experiments were conducted in greenhouse to evaluate the control efficacy to Eleusine indica, Digitaria sanguinalis, Portulaca oleracea, Amaranthus retroflexus and Cyperus rotundus, the safety on different cotton varieties, and the selectivity index between cottons and weeds of the combinations of trifloxysulfuron and quizalofop-p-ethyl. The results showed that combinations of the two herbicides had synergistic or additive activity to C.rotundus and P.oleracea, and additive activity to A.retroflexus, E.indica and D.sanguinalis. When the mass ratio of trifloxysulfuron and quizalofop-p-ethyl was 1:3, 1:4, the mixture was safe to all cotton varieties at application rate of 80 g/hm²; however, when the application rate increased to 160 g/hm², the safety of the mixture to different cotton varieties varied greatly, and the safety to Lumianyan 36 was higher than that to Shannongmian 8. The selectivity index between cottons and weeds of the combinations was significantly higher than that of trifloxysulfuron alone, which suggested combination of trifloxysulfuron and quizalofop-p-ethyl improved the safety on cotton.