4种彩叶植物叶绿素荧光参数日变化研究

以红背桂、花叶鹅掌柴、红龙草和黄金榕等4种彩叶植物为材料，研究其叶片的叶绿素荧光参数日变化。结果表明：在自然光下，4种彩叶植物的叶绿素荧光参数光适应下最大荧光（Fm’）和原初光能转化效率（Fv／Fm）均先降后升，而表观光合电子传递速率（ETR）和非光化学淬灭（NPQ）均先升后降；在中午强光下，4种彩叶植物的叶片均出现了强烈的光抑制，热耗散是其主要的光保护机制；红龙草和黄金榕对光能的利用效率较高，更适应强光环境。

Diurnal variation of chlorophyll fluorescence parameters of four colorful plant species

Diumal variation of chlorophyll fluorescence parameters of Excoecaria cochinchinensis, Schefflera odo＇rata cv. variegate, Al- temanthera Ficoidea cv. ruliginosa and Ficus microcarpa were studied. The results showed that, under the natural light, the chlorophyll fluorescence parameters of Fm＇ and Fv/Fm of the four colorful plant species decreased followed by an＇ increase, whereas those of ETR and NPQ increased followed by a decrease. The leaves of four colorful plants suffered photoinhibition under intense light at noon, and the heat dissipation was the main photoprotective mechanism. A. Ficoidea cv. ruliginosa and F..microcarpa were higher in utilization efficiency of luminous energy than the others, and the formers were more adapted to a higher light environment.