Abstract: An experiment was carried out in Shanghai Haifeng Modern Agriculture Co LTD, to study the effects of different sowing date on plant type and ear characters of direct seeded rice of Huaidao 5, Wuyujing3, Wuyunjing21. The preliminary results were as follows: the best sowing date of direct seeded rice was in early June in Haifeng region. With delayed sowing date, the plant heights, upper internodes, the number of primary branches and secondary branches, the grain number per panicle were decreased, the lower internodes were increased. The delayed sowing date had less effects on ear characters, plant heights and yields of Wuyunjing 21 and Huaidao 5 than that of Wuyujing 3.

Key words: direct seeded rice, variety, sowing date, plant type, ear characters

摘要： 通过研究淮稻5号、武育粳3号、武运粳21号等3个品种不同播期对直播水稻株型及穗部性状的影响，以期塑造直播水稻理想株型。结果表明，在海丰种植条件下，直播水稻最佳播期为6月上旬。随着播期推迟，株高下降，下部节间增长，上部节间变短；同一品种在播期推迟情况下，一次枝梗数、二次枝梗数及每穗粒数均呈减少趋势，不同品种减少幅度存在差异；在推迟播期情况下，武运粳21号、淮稻5号的株高与穗型受到的影响比武育粳3号小，产量的影响也相对较小。

关键词: 直播稻, 品种, 播期, 株型, 穗部性状