摘要
在两种钾水平下,研究了暗处理对缺钾敏感品种的^(14)CO_2同化及同化产物输出的影响。结果表明,经暗处理后,水稻植株对CO_2的固定,孕穗期在两种钾水平下均明显下降;灌浆期低钾植株CO_2固定明显降低。常量钾处理的标记植株的总放射性活度高于低钾处理的植株,并随暗处理时间的缩短而增加,光与钾有助于光合产物向谷粒中分布。叶片中糖含量,灌浆期多于孕穗期。在自然光照下,常量钾植株的含糖量多于低钾处理,暗处理则低钾多于常量钾处理。叶片中ATP含量,在正常光照与暗处理下低钾处理均高于常量钾处理。暗处理与人工24小时光照使标记叶光合产物的输出量减少,而钾营养则促进光合产物的输出。
The effects of darkness on 14CO2 assimilation and photosynthate exported out of leaf in low-potassium sensitive veriaty of rice grown at two potassium level were studied. The results showed that at both booting stage and grain-filling staage.dark treatment considerably decreased CO2 assimilation of leaves in rice plant,furthermore at the later stage low-potassium level aggravated the effect of darkness. The total radioactivity of 14C assimilated into rice plants grown at normal potassium level was higher than that in rice plants grown at low-potassium level,which increased as dark time decreased. Light and potassium facilitated distribution of photosynthate into grains. The soluble carbonhydrate content in leaves of rice plant at grain-filling stage was higher than that at booting stage. Under natural light condition leaf soluble carbonhydrate content in plants grown in normal potassium level was higher than in low potassium level,while under darkness opposite results were observed. The ATP contents in leaves of rice plants grown in low potassium level were higher than that in plants in normal potassium under both natural light and darkness. 24 h light treatment after dark treatment reduced export rate of photosynthate from leaves,whereas potassium promoted the photosynthate export.
基金
农业部"八五"重点课题资助
关键词
水稻
暗处理
钾
同化物
dark treatment
potassium nutrition
photosynthate export
