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大豆是天津市南部大港区王庄镇主要作物品种。２００１年夏播面积占总播种面积一半以上。草害严重威胁着大豆的生长，制约产量的提高。经过田间调查，夏播大豆田杂草以一年生禾本科杂草为主要群落，占田间杂草数量的６０％～７０％，其主要种类为马唐、狗尾草、稗草等；阔叶杂
Soybean is the main crop variety in Wangzhuang Town, Dagang District, southern Tianjin. Summer sowing area in 2001 accounted for more than half of the total sown area. Grass serious threat to the growth of soybean, limiting the yield increase. After field investigation, weeds in summer sowing soybean grass weeds as the main annual community, accounting for 60% to 70% of the number of field weeds, the main species Crabgrass, Setaria, barnyard grass; broadleaf miscellaneous