中文摘要：

在免耕条件下，对3种水分管理模式（水层淹灌、干湿交替灌溉和湿润灌溉）的立苗期根系特性进行了研究。结果表明，除抛栽后第2天，无论晚季或早季，整个立苗期干湿交替灌溉处理的根冠比、单株根生物量、总根数、白根数、一次分枝数量、根系活力、发根力均显著或极显著高于水层淹灌和湿润灌溉处理。水层淹灌处理利于二次分枝根的发生与根系的伸长。湿润灌溉处理更能促进早季稻根毛区生长。

英文摘要：

The effect of different moisture management modes on root growth characteristics during seedling standing period under no-tillage was studied. Results showed that the rice ratio of root to shoot dry weight,root dry weight, root number, whiter root number, root primary branches, root activity and root growth abilities of alternation irrigation were significantly or greatly significantly higher（P〈0. 01, P〈0.05）than those of wetting irrigation and water layer irrigation except the second day after seedling throwing. Wetting irrigation had positive effect on root secondary branch roots and root length;water layer irrigation hastened the growth of root hair zone length in early season.