【摘要】 以水稻为材料 ,对其在不同自然条件下和不同处理下的光合速率日变化进行了研究 ,结果表明 :连续晴天条件下 ,其光合速率日变化为典型的双峰曲线 ,而连续雨天后初晴 ,其光合速率日变化为单峰型。全光照和反光周期处理 4d的植株 ,其光合速率日变化曲线与未处理 (对照 )的植株比较 ,既相似又发生了一定变化。而经 8d处理后 ,全光照处理的夜晚也能进行光合作用 ;反光周期处理的白天光合作用很弱 ,而夜晚能正常进行光合作用。说明水稻光合速率日变化也受内生节奏的调节 ,这种节律转换的处理时间大约 8d以上。更多还原

【Abstract】 Using paddy rice as materials, the daily changes of photosynthetic rate under different natural conditions and different photoperiod treatments are examinated. Results show that the daily change of photosynthetic rate in shining day is double peak curve, but in the first shining day after several raining days it is single peak curve. Under short time(4 days’) all day illumination or contra photoperiod treatments, it runs with the original rhythm, but under long time (8 days) treatments, it develops a new rhythm adpated to the new condition. The phase change of this rhythm needs 8 days above. Thus, we conclude that the daily change of photosynthetic rate is influenced by external conditions as well as regulated by endogenous rhythm.\;更多还原