扁禾旱 蔗草的生物学特性及防治研究

 研究表明，扁秆藨草生育节律明显，有性繁殖对季节要求严，无性繁殖对季节要求宽，在“半遮光”条件下不能抽穗结实，无性繁殖受到抑制。扁秆藨草的阶段发育与叶龄相关显著，用主茎叶龄预测再生苗的线性回归方程式：?a=-36.74+6.24x(1983)和Ya=-32.42+6.28x(1984年)；预测块茎发生量的线性回归方程式：?t= -67.97+10.12x(1983年)和Yt=-33.91+80.4x(1984年)。机械和人工除草可抑制块茎的形成和阻止抽穗结实，但能促进再生苗的蔓延。大田防治必须在扁秆藨草块茎形成之前用药，并做到株株受药，才能起到“斩草除根”的作用。扁秆藨草的发生分布与耕作栽培制度关系密切，实生苗萌发迟而集中，再生苗萌发早而分散，是防除的主要对象。实验表明，只有运用农业、生物、化学等综合防治手段，才能有效地控制扁秆藨草的为害。

A Study on Biology of Flatstalk Bulrush and its Control

Flatstalk Bulrush is a perennial, notorious weed which spreads over the paddy-rice fields and lowlands in the world. It has a distinct growth rhythm. Its sexual reproduction is more limited than vegetative propagation in relation to the growing season. Under the semi-sunshine condition, it cannot produce seeds, and its vegetative propogation is retarded.The stage of development of Flatstalk Bulrush is correlated to leaf age. The equation of linear regression of its regrowths can thus be predicted by the leaf age of main stalks as: ?a= –36.74+6.24x (1983), and ?a= –32.42+6.28x (1984) ; The equation of linear regression for predicting its tuber is. ?t= –67.97+l0.12x (1983) , and ?t= –33.91+ 8.04x (1984). The weed control with machine and man-power can suppress forming tuber and producing seeds but help its regrowths spread out.The occurrence and distribution of Flatstalk-Bulrush are correlated with cropping system. The emergence of its seedling is later and concentrated than its regrowths which are the main object to control. The farm practices show that the better way to kill the weed is an integrated control, i. e. the combination of agricultural, biological chemical and other methods as well.