光照对盾叶薯蓣荧光光谱和叶绿体结构的影响

Effect of Light Intensity on Fluorescence Spectra and Chloroplast Structure of Dioscorea Zingiberensis

对生长在10,55,100,270μmol·m-2·s-1光强下弱光生态型盾叶薯蓣的长期适应性进行了测定.结果表明,生长光条件不同其77K荧光峰也出现明显的变化.弱光条件(10,55μmol·m-2·s-1)下无F595和F740荧光峰(55μmol·m-2·s-1下有F740肩峰),但有F720主峰;能量主要分配到光系统II;暗适应后引起了LHCII和CP43组成的功能发生改变;红光诱导分配到光系统II的能量比例下降;类囊体膜折叠指数较大,淀粉粒较小.较强光条件(100,270μmol·m-2·s-1)下77K荧光光谱无F720,但有F740峰较强;光系统II的激发能量较强;暗适应后增加了LHCI到PSI-RC的传递效率;红光诱导分配到光系统II的能量比例下降;类囊体膜折叠指数较小,淀粉粒较大.

The long adaptations of Dioscorea zingiberensis type low-light intensity to 10,55,100 and 270μmol·m^-2·s^-1 light were tested. The results showed that the fluorescence spectrum was different as the growth light was different, In dark growth light （10 and 55μmol·m^-2·s^-1）, the spectra of the D. zingiberensis type low-light intensity had not F595 and F740 fluorescence peaks （in 55μmol·m^-2·s^-1 had F740 shoulder peak）, but had the F720 main peaks. The energy were mainly distributed to photosystem Ⅱ. Dark adaptation changed the function of LHCⅡ and CP43. Red light of 670 nm and 716 nm induced for 15 rain decreased the energy distributed to photosystem Ⅱ. The stacking index of chloroplast was larger than those in the higher growth light （ 100 and 270μmol·m^-2·s^-1）, but the starch grain was smaller. In the higher growth light （ 100 and ：270μmol·m^-2·s^-1）, the spectra of the D. zingiberensis type low-light intensity had not F720, but the F740 main peaks were stronger. The excited energy of photosystem Ⅱ was stronger. Dark adaptation increased the energy transfemng efficiency from LHCt to PSI-RC. Red light of 670 nm and 716 nm induced for 15min increased the energy distributed to photosystem Ⅱ. The stacking index of chloroplast was smaller, but the starch grain was larger.