金边黄杨和大叶黄杨的光能吸收分配特征及其机制分析

Mechanism in light energy absorption and distribution between Euonymus japonica cv. Aureo-ma and Euonymus japonica

以金边黄杨和大叶黄杨为试材,从光的吸收反射、色素含量、吸收光能的分配利用等方面进行研究.结果表明,金边黄杨的黄色区域具特殊的物理特性,横切面较薄,对光能的反射较多而吸收较少,且色素含量(Chla,Chlb和Car)显著低于其正常的绿色区域.金边黄杨与大叶黄杨绿色区域对光能的分配利用不同,大叶黄杨吸收的光能多用于光化学反应(ФPSⅡ),而金边黄杨则更多地用于热耗散(ФNPQ),这可能与金边黄杨较高的叶黄素循环库(A+Z+V)值有关.光抑制处理后,金边黄杨相对大叶黄杨虽未表现出较强的光保护能力,但是对光抑制过程中的光损伤修复能力较强.

We analyzed the differences in light absorption and reflection, pigments contents, distribu- tion of light energy absorbed between Euonymus japonica cv. Aureo-ma and Euonymus japonica. The results were as follows： 1. the yellow margin of Euonymus japonica cv. Aureo-ma showed more reflec- tion while less absorption in light, thinner ransverse section and less pigment contents （ Chla, Chlb and Car） ; 2. light energy absorbed was distributed more to photochemical efficiency （ФpsⅡ） in E. japoni- ca, whlie more to quantum efficiency of regulated （ ФNpQ ） in Euonymus japonica cv. Aureo-ma. The more distribution in regulated thermal dissipation comes from higher content of xanthophyll cycle pool （A ＋ Z ＋ V） , which would offer Euonymus japonica cv. Aureo-ma more effective in dissipating extra light energy than Euonymus japonica. After being treated with high light, Euonymus japonica cv. Au- reo-ma did not show strong photoprotection from photoinhibition, but restored quickly from photoinhibition.