外源山梨醇对盐胁迫下两优培九和武运粳7号光合特性及类囊体膜多肽组分的影响

 以4叶期的水稻幼苗为材料，比较研究了外源山梨醇处理对盐胁迫下两优培九和武运粳7号幼苗光合特性及类囊体膜多肽组分的影响。研究结果表明，随着盐处理浓度的增加，两优培九和武运粳7号的叶绿素含量、PSⅡ的电子传递活性、叶绿体放氧活性、光合速率呈下降趋势；叶绿体ATP含量、 叶绿体ATP酶(Mg2＋ATP酶和Ca2＋ATP酶)活性先升后降，PSⅠ的电子传递活性、呼吸速率则呈上升的趋势；但类囊体膜的多肽组分并不存在明显的差异。相比之下，两优培九对盐胁迫的抗性大于武运粳7号，具有一定的高产优势。外源山梨醇对两种水稻抵抗盐胁迫具有一定的缓解作用。

Effect of Exogenous Sorbitol on Photosynthetic Characteristics and Polypeptide Compositions of Thylakoid Membrane of Liangyoupeijiu and Wuyunjing 7 under Salt Stress

Photosynthetic characteristics and polypeptide compositions of thylakoid membrane in four-leaf-stage rice seedlings of Liangyoupeijiu and Wuyunjing 7 under salt stress were studied when rice plants were sprayed with sorbitol. With increase of salt concentration, chlorophyll content, electron transport activity of PSⅡ, the O₂ evolution of chloroplast and photosynthetic rate decreased, the ATP content in chloroplast, ATPase activity of chloroplast first boosted up and then dropped, but electron transport activity of PSⅠ, respiration rate enhanced. There were not obvious differences on the polypeptide compositions of thylakoid membrane. The resistance to salt stress in Liangyoupeijiu is obviously stronger than that in Wuyunjing 7. Exogenous sorbitol has some mitigative functions to salt stress.