低叶绿素含量对突变体水稻吸收光能分配特性的影响

Effect of Low Content Chlorophyll on Distribution Properties of Absorbed Light Energy in Leaves of Mutant Rice

研究了田间条件下低叶绿素含量水稻突变体及其野生型的PSⅡ光化学效率、热耗散速率等一系列与光化学反应有关的生理过程的日变化,并分析了二者在1d中对吸收光能分配的差异。结果表明,突变体水稻叶片因截光率小而限制了其对光能的吸收,但由于它的电子传递速率比野生型的高,因而部分缓解了它吸收光能不足的不利效应;与野生型水稻相比,突变体水稻叶片所吸收的能量中分配给光化学反应途径的能量较多,而过剩的激发能较少。

The diurnal variations of photochemical efficiency of PSII, heat dissipation rate and other physiology process inlow content chlorophyll mutant rice were studied under field conditions. The difference of the absorbed light distribution betweentwo rice varieties in a day was also assessed. Results showed that the mutant had poor absorbed light because of its little lightabsorption coefficient, but higher electron-transferring rate could partly reduce the disadvantageous effect of deficient absorbedlight in mutant. Compared with wild-type rice, the mutant had less excess excitation energy and the fraction of absorbed lightallocated to photochemical process was more.