砜吡草唑除草活性及对玉米的安全性评价

Herbicidal Activity and Safety Evaluation of Pyroxasulfone in Maize Fields

砜吡草唑是一种新型、高效、广谱的土壤处理除草剂,为探究其对玉米田常见杂草的除草活性及对玉米的安全性,通过室内生物测定和田间药效试验测定砜吡草唑的杀草谱、除草活性及其对玉米的安全性。室内生物测定结果表明,砜吡草唑在90 g(a.i.)/hm^(2)时,对牛筋草、马唐、狗尾草、稗草、碎米莎草、青葙、铁苋菜等多种常见秋熟作物田杂草均具有较好活性,鲜重抑制率均大于90%;对4种常见玉米田杂草马唐、稗草、青葙、碎米莎草的GR_(50)分别为14.77、16.41、15.37、27.74 g(a.i.)/hm^(2),除草活性在供试剂量下均高于对照药剂精异丙甲草胺。砜吡草唑在供试的3个玉米品种奥玉510、郑单958、蠡玉16和4种杂草马唐、稗草、青葙和碎米莎草之间具有较好的选择性,选择性指数为23.82~240.88。田间药效试验表明,砜吡草唑在250 g(a.i.)/hm^(2)时,对马唐、稗草、铁苋菜、碎米莎草的总鲜重防效达91.4%,对供试玉米蠡玉16安全。

Pyroxasulfone is a new,efficient and broad-spectrum pre-emergence herbicideHerbicidal activity against common weeds in maize fields and its safety to maize was studied by the greenhouse and field experiments.The results showed that in the treatment dose of 90 g(a.i.)/ha,Eleusine indica,Digitaria sanguinalis,Setaria viridis,Echinochloa crus-galli,Cyperus iria,Celosia argentea,Acalypha australi and other common weeds in variety of fields autumn crops were achieved control effect of above 90%.Among them,four kinds of maize field weed D.san⁃guinalis,E.crus-galli,C.argentea,C.iria had better control effects,with the GR_(50) of 14.77,16.41,15.37,27.74 g(a.i.)/ha.Herbicidal activity was higher than s-metolachlor of the control agent.The selectivity index of pyroxasul⁃fone between three tested maize varieties and four species of weeds were among 23.82 to 240.88,which showed that it has a higher selectivity between maize and weeds.The field test results of pyroxasulfone showed that,at the recom⁃mended dose in the field,pyroxasulfone had a control effect of 91.4%against D.sanguinalis,E.crus-galli,Acaly⁃pha.australi,C.iria.And it was safe for the test maize variety Liyu 16.