Abstract: Using indica japonica hybrid rices of Ⅱyou2070, Ⅱyou419 and their restorer lines 2070, Zhong419 as materials, the changes of root exudate after initial heading stage were studied. The results show that root activity of indica japonica hybrid rices were higher than their restorer lines, especially from initial heading stage to milk ripening stage, however, the amount of root exudate rapidly decreased after milk ripening stage. This dynamic change was consistent with the photosynthesis rate and chlorophyll content of leaf at different levels and green leaf areas above the ground.

Key words: hybrid rice, root, exudates, leaf, physiological function

摘要： 对籼粳亚种间杂交稻Ⅱ优2070、Ⅱ优419及其恢复系2070、中419始穗后伤流液的变化进行了分析，结果表明亚种间杂交稻具有较高的根系活力，突出表现在始穗期至乳熟期，其后伤流液量明显下降且幅度较大，这种变化趋势与地上部不同叶位叶片光合速率、叶绿素含量和绿叶面积的变化相一致。

关键词: 杂交水稻, 根系, 伤流液, 叶片, 生理功能