稻田眼子菜的生物学特性与化学防除

眼子菜(Potamogeton tepperi A.Benn.)是我省稻田中普遍发生的多年生恶性杂草,为害严重,人工很难除尽。本文是1972—1973年的研究结果。对眼子菜的形态特徵,特别是根茎与茎芽,作了详细的观察和描述。通过研究其分布与为害、发生周期、繁殖与蔓延、各生育期的特点等生物学特性,明确了支茎初发绿叶时,开始进入光合营养期,此时植株幼嫩,抗药力弱,为化学防除的有利时期。试验确定了扑草净、利谷隆、敌草隆、西草净等除草剂在我省各类稻作区安全、高效的用量范围以及混用方法。以昆明地区为例,模拟分析药性、草情、苗情、环境特点的相互关系,提出栽秧后20—40天为我省施药适期范围,以眼子菜由红叶期转入绿叶期时为指标,并经实践验证,这是可靠的。因地制宜地掌握用药量和施药适期,管好田水,可获得安全、高效、经济与省工、增产的效益。在全省已大面积推广应用,深受群众欢迎。

THE BIOLOGICAL CHARACTERISTICS OF POTAMOGETON TEPPERI A.BENN.AND ITS CHEMICAL CONTROL IN PADDY FIELDS

The Potamogeton tepperi A.Benn.is the most noxious weed in paddy field in Yunnan province and causes great damage to the rice crop.It is very difficult to eradicate it by manual cultivation.This report is concerned with the investigations about the weed and its chemical control conducted in 1972 to 1973.The biological characteristics of potamogeton tepperi A.Benn.,especially those of the rhizomes and rhizome buds were observed and described in detail.Taking into consideration the interrelations between the growing stages of weed and crop,the weather conditions and the natures of herbicides,the suitable period for application is suggested at 20-40 days after transplantation,when the leaves of weedlings are turning from red to green,which is pointed out as a morphological index of application time.The experiments have provided the safe and effective dosages for applying herbicides such as prometryne,linuron,diuron,simetryne and their combination formulas.A list is given of the measures of controlling the weeds for various regions of our province,practices on a large scale have demonstrated their practical worth,and now they are adopted universally by commume members.