Abstract: Pot experiment was conducted in 2000-2001. Results showed that water stress reduced rice yield significantly within 25 days after 80% of full heading; the effects were very weak after 25 days due to water in soil could maintain rice physiological activity about 10 days. The grain quality interrelated to the grain filling degree. It was better to keep water in paddy until 25 days after 80% of full heading for rice quality cultivation.

Key words: rice, water stress, yield, grain quality, pot culture

摘要： 2000~2001年设置盆栽试验，在人为控制水分的条件下，造成水稻齐穗后遭受干旱的条件，研究了花后水分亏缺对稻谷产量和稻米品质的影响。结果表明，水稻齐穗后25 d内，是水稻产量形成的关键时期，这一阶段干旱缺水，将对稻谷产量产生重大影响；齐穗25 d以后断水，由于土壤田间持水量尚能供应10 d左右的生理需水，影响大幅减弱。稻米品质与谷粒的充实程度显著相关，在进行优质稻的栽培中应尽量保持后期的田间水分，排水时间不能早于齐穗后25 d。

关键词: 水稻, 水分胁迫, 产量, 稻米品质, 盆栽试验