超级稻P88S/0389光合特性初探

目的]通过比较超级稻P88S/0389与其亲本P88S和R0389剑叶的光合特性,探索P88S/0389高产的光合机理。方法]采用W ellburn和Lichenthaler的方法测定剑叶叶绿素及类胡萝卜素含量,并使用便携式光合测定仪测定光合速率及叶绿素荧光参数。结果]杂交种的叶绿素含量居于双亲之间,生育期前期偏母本而后期偏父本;同时,杂交种有较强的光能吸收、转化和碳固定能力,其剑叶的净光合速率(Pn)、PSⅡ活性(FV/FO)和PSⅡ原初光能转化效率(FV/Fm)、叶绿素荧光光化学猝灭系数(qP)等参数均高于亲本,且下降速率都比亲本慢,非光化学猝灭(qN)较亲本低,上升速率也比亲本慢,表现出不易早衰等超亲优势。结论]杂交种P88S/0389吸收的光能主要用于光化学反应,热耗散较少。在水稻生产中,选择同时具有较高光合速率和较长的光合速率高值持续期的品种对水稻的高产尤为重要。

Preliminary Study on the Photosynthetic Characteristics of Super Hybrid Rice P88S/0389

Objective] The aim of this study is to understand the high yield photosynthetic mechanism of super hybrid rice P88S/0389.Method] Chlorophyll and carotenoid contents were measured via the method of Wellburn and Lichtenthaler,and the photosynthetic rate and chlorophyll fluorescence parameters were measured using portable photosynthesis system.Through the comparison of above measured indices between P88S/0389 and its parents,the photosynthetic characteristics were obtained.Result] The pigment content of P88S/0389 lied between their parents,and detailedly was closer to its female parent at earlier growth stage and to its male parent at latter stage,respectively.The Pn,FV/F0,FV/Fm and qP of the flag leaf of P88S/0389 were all higher than those of its parents,while the degradation rates of these parameters were slower than that of its parents.The qN of flag leaf was lower than that of its parents,and the increasing rate of qN of P88S/0389 is also slower than that of its parents,indicating the great heterosis of P88S/0389 to its parents in photosynthetic capacity.The data show that P88S/0389 is endowed with stronger capacities in light energy Absorption,transformation and carbon fixation compared to its parents.Conclusion] The light energy Absorbed by hybrid mainly contributes to photochemical reaction,and little for heat dissipation.For ensuring high yield,the rice cultivars selected for production should synchronously present higher photosynthetic rate and longer high value duration.