长江中下游小麦田杂草发生组成及群落特征

为明确我国长江流域冬小麦田杂草发生情况,采用倒置“W”方法取样对江苏、安徽和湖北省945个冬小麦田杂草进行了抽样调查。结果表明,长江流域冬小麦田共发现杂草93种(变种),隶属于28科72属,其中禾本科杂草最多,有15种;其次是菊科杂草有12种;蓼科杂草9种;十字花科7种;豆科和车前科各6种;石竹科5种。其中优势杂草有猪殃殃、日本看麦娘、看麦娘、菵草、野老鹳草、牛繁缕6种;区域性优势杂草有17种,常见杂草有12种,一般杂草有58种。根据物种多样性指数、辛普森指数及均匀度指数分析,孝感、阜阳、襄阳和宿州地区小麦田杂草群落的物种多样性较高,宣城地区多样性最低。Sorensen’s相似度指数聚类结果发现,江苏北部地区麦区杂草组成与安徽北部相似。各地小麦田杂草群落结构与组成的差异与气候条件、种植模式及除草剂应用等有关。

Weed species composition and characterization in wheat fieldsalong the middle and lower Yangtze River

The weed species distribution and occurrence in winter wheat field along Yangtze River were surveyed by sampling methods of inverted W-pattern.The weed species numbering 93(including varieties)belong to 28 families and 72 genera,and the diversity and composition of weed communities were determined in 945 wheat fields.The most abundant taxa consisting of 15 weed species were found from family Poaceae,followed by 12 species from Asteraceae,nine species from Polygonaceae,seven species from Brassicaceae,six species from Fabaceae and Plantaginaceae each,five species from Caryophyllaceae.Among them,six species,Galium spurium,Alopecurus japonicus,Alopecurus aequalis,Beckmannia syzigachne,Geranium carolinianum,Myosoton aquaticum were considered as dominant weeds,17 species regional dominant weeds,12 common weeds and 58 normal weeds.The species richness,diversity and evenness of weed community in winter wheat fields in Xiaogan,Fuyang,Xiangyang and Suzhou were higher than those in other regions,and the lowest region was Xuanzhou.Based on the Sorensen’s similarity index,the structure of weed community in north Anhui region was similar to that of north Jiangsu province.The difference of weed distribution and community structure might result from the climatic condition,crop rotation and weed management practices.