不同林冠环境下顶花板凳果生理适应性研究

摘要

以顶花板凳果(Pachysandra terminalis Sieb.et Zucc)为研究对象,在不同人工林冠环境下种植,对比分析叶片色素含量和光合能力的差异.结果表明:林缘与林下交界处的BD2和BD4叶片中总叶绿素、叶绿素a、b和类胡萝卜含量均显著高于其他叶片,尤其BD4叶片各光合色素含量均极显著高于林外的BD8(P ＜0.01);林外BD8和林缘BD6叶片叶绿素a/b值接近3,但叶片中叶绿素和类胡萝卜素含量相对较低,其他顶花板凳果叶片叶绿素a/b值在(2.093±0.249)～(2.589±0.019);林缘与林下交界处BD2和BD4叶片的净光合速率高于林缘BD5、林外BD8和林下BD1;BD2叶片瞬间光能利用率极显著高于林外BD8和林缘BD5叶片(P＜0.01),并显著高于林下的BD1和BD3(P ＜0.05),BD4叶片叶室内光合作用有效辐射占外界光合作用有效辐射的比例显著高于其他样叶(P＜0.05).顶花板凳果最适宜在半阴的环境中种植,BD2和BD4高含量的叶绿素及合适的叶绿素a/b值也使顶花板凳果的叶片呈现深绿色,叶片色彩和质地更健康,林外BD8叶片叶绿素含量的下降及蒸腾速率的升高使植株叶片呈现出黄绿色.%The differences of leaf pigment content and photosynthetic ability of Pachysandra terminalis Sieb.et Zucc under different artificial canopy conditions were studied.The results showed that the contents of total chlorophyll,chlorophyll a,chlorophyll b and carotenoid in the leaves of BD2 and BD4 at the junction of forest edge and forest were significantly higher than those of the other leaves,especially the photosynthetic pigment content in the leaves of BD4 was significantly higher than the leaves of BD8 which was out of the forest(P ＜ 0.01).The chlorophyll a/b value in the leaves of BD8 and BD6 was close to 3,and the other Pachysandra terminalis Sieb.et Zucc leaves was (2.093 ±0.249)-(2.589 ±0.019).The contents of chlorophyll and carotenoid in the leaves was relatively low.The leaf photosynthetic rate of BD2 and BD4 at the junction of forest edge and forest was higher than that of BD5,BD8 and BD1.The leaf light utilization rate of BD2 was significantly higher than that of BD8 and BD5 (P ＜ 0.01) as well as BD1 and BD3 (P ＜ 0.05).The rate of leaf indoor photosynthetically active radiation in the leaves of BD4 was significantly higher than that of the other samples.Because of the high content of chlorophyll and suitable chlorophyll a/b value in leaves of BD2 and BD4,the leaves had dark green leaf color and healthier texture.Pachysandra terminalis Sieb.et Zucc was most suitable for planting in semi shade environment.Due to decreased chlorophyll content and increased transpiration rate in the leaves of BD8,the leaf color of Pachysandra terminalis Sieb.et Zucc appeared yellow green.