砜吡草唑与嗪草酮复配应用于大豆-玉米带状复合种植田的效果评价

Effect of combination of pyroxasulfone and metribuzin in maize and soybean intercropping patterns

为明确小麦Triticum aestivum田新型除草剂砜吡草唑与嗪草酮复配应用于大豆Glycine max玉米Zea mays带状复合种植田的可行性,在温室内采用Gowing法测定砜吡草唑与嗪草酮复配的联合作用类型,并通过盆栽法测定两者复配制剂80%砜吡·嗪草酮水分散粒剂(water dispersible granule,WDG)的杂草防除谱以及对大豆和玉米的安全性。结果显示,砜吡草唑与嗪草酮复配防除禾本科杂草马唐Digitaria sanguinalis和稗Echinochloa oryzicola的联合作用类型属于增效作用;对阔叶杂草苘麻Abutilon theophrasti和龙葵Solanum nigrum的联合作用类型属于加成作用。80%砜吡·嗪草酮WDG对6种禾本科杂草马唐、稗、牛筋草Eleusine indica、狗尾草Setaira viridis、虎尾草Chloris virgata、大狗尾草Setaira faberii和4种阔叶杂草马齿苋Portulaca oleracea、青葙Celosia argentea、铁苋菜Acalypha australis、反枝苋Amaranthus retroflexus的防除效果均很好,其GR50在6.1~21.6 g(a.i.)/hm^(2)之间,GR90在16.3~50.5 g(a.i.)/hm^(2)之间,对苘麻和龙葵的防除效果略差,其GR50分别为53.3 g(a.i.)/hm^(2)和25.4 g(a.i.)/hm^(2),GR90分别为282.1 g(a.i.)/hm^(2)和96.7 g(a.i.)/hm^(2),低于其田间推荐剂量300~360 g(a.i.)/hm^(2),且该药剂对玉米和大豆的安全性都很高,在玉米与马唐、稗、牛筋草、马齿苋、青葙及铁苋菜这6种杂草之间的选择性指数均大于13.6,在大豆与这6种杂草之间的选择性指数均远大于28.5。表明砜吡草唑完全可与嗪草酮复配应用于大豆-玉米带状复合种植田的杂草防除。

Pyroxasulfone is a new herbicide registered to be used in wheat field,but it has not been registered for use in soybean or maize field.In order to determine the feasibility of the combination of pyroxasulfone and metribuzin in maize and soybean intercropping patterns,the combined action mode of pyroxasulfone and metribuzin was determined with Gowing method in greenhouse,at the same time,the weed control spectrum of 80%pyroxasulfone·metribuzin water dispersible granule(WDG)and the safety of soybean and corn were tested in greenhouse.The results showed that pyroxasulfone+metribuzin was synergistic in controlling Digitaria sanguinalis,Echinochloa oryzicola and additive in controlling Abutilon theophrasti,Solanum nigrum.Pyroxasulfone·metribuzin 80%WDG was highly effective against six grasses D.sanguinalis,Eleusine indica,Ec.oryzicola,Setaira viridis,Se.faberii,Chloris virgata and four broad-leaved weeds Portulaca oleracea,Acalypha australis,Amaranthus retroflexus,Celosia argentea with GR506.1-21.6 g(a.i.)/hm^(2) and GR9016.3-50.5 g(a.i.)/hm^(2),and slightly effective against Ab.theophrasti,So.nigrum with GR5053.3,25.4 g(a.i.)/hm^(2) and GR90282.1,96.7 g(a.i.)/hm^(2) respectively.It had sound safety to maize and soybean,and the selectivity index was greater than 13.6 between maize and main weeds,than 28.50 between soybean and main weeds.The results indicated that pyroxasulfone could be fully applied with metribuzin in maize and soybean intercropping patterns.