稗草主要生物学特性及其防除

本文概述了稗草(Echinochlon spp．)的生物学特性及其防除效果。试验证明稗草萌发的最低温度为12℃，稗草种子在充足的水分条件下，当有效积温达33.8—49.5℃(生物零度为10℃)时，出现田间稗草的发生高峰期。提出消除稗草要从秧田入手，并应掌握在稗草3叶期以前、化学防除应以药效期相吻合，才能达到预期的效果。通过试验对9种除草剂进行了综合评价，实践证明化学防除配套技术和农业措施协调应相结合，能有效地控制稻田稗草的危害。

STUDIES ON THE BIOLOGICAL CHARACTERISTICS OF ECHINOCHOLA CRUSGALLI AND ITS CONTROL METHODS

Echinochloa spp., which was a annual weed belonging to Gramineae and had strong adaptibility and wide distribution, was one of the staple noxious weeds in rice, wheat and soybean fields. The author studied the biological characteristics of Echinochloa crusgalli and its controlling methods in rice fields since 1975. It has been shown that the initial temperature for its germination and the optimal temperature for its growth were found to be 12℃, and 30—35℃ respectively. The emergence peak of Echiochloa cursgalli would be predicted by two indices i.e. accumulated temperature biological zero = 10℃ and leaf age. The former was 33.8—49.5℃ when the soil moisture was sufficient and the latter was oneleaf age of Echinoloa crusgalli after puddling. The experiment results also pointed out that the control of Echinochloa crusgalli in rice field should begin with the control in nursery bed and the key to success was to make the effective stage of herbicides coincide with the emergence peak (sensitive stage) of weeds: The chemical control by herbicides such as butachlor, thiobencarb, molinate, oxidizon, dimethametyn (piperophos), pretilachlor and quinclorac combined with agricultural practice such as cleaning up seeds and water management, etc. may result in optional weed control.