【作者】 王强； 赵学平； 吴长兴； 戴芬； 冯克强；

【Author】 WANG Qiang;ZHAO Xueping;WU Changxing;DAI Feng;FENG Keqiang;Institute of Plant Protection,Zhejiang Academy of Agricultural Sciences;Jiaxing Academy of Agricultural Sciences;

【机构】 浙江省农业科学院植物保护研究所； 浙江省嘉兴市农业科学院；

【摘要】 1996~1997年在浙江嘉兴定点调查了湿润直播稻田杂草出苗动态和发生规律,同时比较了直播与移栽田,早稻、单晚与连晚直播田,翻耕与免耕直播田之间杂草发生的差异。浙北地区湿润直播稻田杂草发生以稗草、千金子、异型莎草、节节菜、陌上菜为主,其次有通泉草、丁香蓼、水芹。其中,禾本科、莎草科和阔叶杂草的种类数分别占25.0%、18.8%和56.2%,出苗数量分别占11.2%、11.6%和77.2%。单晚直播田稗草、千金子发生重于其他直播田,直播田稗草和千金子的数量明显高于移栽田。各类直播稻田杂草于播种后3~4天陆续出苗,1~3周时达到高峰。连晚直播田在播后6~8周还出现明显的第二个出苗高峰。以阔叶杂草为绝对优势的翻耕直播田杂草发生重于免耕田。各类直播田杂草发生数量的自然消长呈现与出苗动态相同的趋势。直播田杂草发生比移栽田提前1个半月,并以稗草、千金子、丁香蓼较早,节节菜、陌上菜、通泉草次之,异型莎草和水芹较迟。稗草、千金子及其他几种主要杂草出苗高峰均呈单峰状态,而节节菜、陌上菜在连晚直播田的出苗则为双峰。更多还原

【Abstract】 Emergence trend and number fluctuation of weeds were observed in fields of wet seeded rice in Jiaxing,Zhejiang in 1996 ~ 1997.Echinochloa cms- galli,Leptochloa Chinese,Cyperus difformis,Rotala indica,Lindernia procumbens were five main species of weeds,and Mazus japonicus,Ludwigia pwstrata,Oenanthe atolonifera and some other weeds were also found in the fields.Numbers of species of grasses,sedges and broadleaf weeds were,respectively,25.0%,18.8%,and 56.2%of total weed species and numbers of emerged seedlings of grasses,sedges,and broadleaf weeds were,respectively,11.2%,11.6%,and 77.2%of total emerged seedlings.E.cms- galli and L.chineses were more common in one season rice fields than in other fields,and there were more M.japonicus,L.procumbens,and O.atolonifera in early rice fields than in late rice fields.Compared with transplanted rice fields,E.crusgalli and L.chinese were more and Eleocharis plantagineiforrnis,Monochoria vaginalis,O.atolonifera and Ceratophyllun demersum were less in the fields of direct seeded rice.Weeds started to emerge in the fields 3 to 4 days after seeding rice.Emergence peaks appeared in 1 ~ 3 weeks after seeding.For late direct seeded rice fields,the second peak of weed emergence appeared in 6 ~ 8 weeks after seeding.In the fields of direct seeded rice with tilling cultivation where broadleaf weeds composed the majority of weed community,number of weeds is larger than in non- tilling field.The number fluctuation of weeds in direct seeded rice fields showed the same trend as emergence of weed seedlings.Weeds emerged one and half month earlier in direct seeded rice fields than in transplanted rice fields.In direct seeded rice fields,E.crus-galli,L.chinese,L.pwstrata emerged earliest,followed by R.indica,L.procumbens,M.japonicus and then by C.difformis,O.atolonifera.For E.cms- galli,L.Chinese and other weeds only one peak appeared,while for R.indica and L.procumbens the second peak was obvious in the fields of late direct seeded rice.更多还原