【摘要】 研究了不同光照条件下3年生曼地亚红豆杉幼苗的光合生理特性,结果表明:自然光、1层遮荫、2层遮荫条件下生长的曼地亚红豆杉光饱和点分别为:887μmol·m-2·s-1,763μmol·m-2·s-1,650μmol·m-2·s-1;光补偿点分别为117μmol·m-2·s-1,96μmol·m-2·s-1和87μmol·m-2·s-1.遮荫增加了幼苗叶绿素含量,而叶绿素a的含量A与叶绿素b的含量B的比值降低,光呼吸速率升高,暗呼吸速率降低.1层遮荫下生长的幼苗叶绿素含量、表观量子效率、叶片厚度、叶面积及生物量最高.1层遮荫(50%透光率)的环境是曼地亚红豆杉在重庆低海拔地区较适宜的光环境.更多还原

【Abstract】 The photosynthetic physiological characteristics of 3yearold Tmedia cvHicksii grown at different light conditions are studied. The results showed that the light saturation points of Tmedia cvHicksii grown at natural light condition, onelayer shady and twolayer shady light conditions are 877 μmol·m-2·s-1, 763 μmol·m-2·s-1 and 650 μmol·m-2·s-1 respectively; and light compensation points are 117 μmol·m-2·s-1, 96 μmol·m-2·s-1 and 87 μmol·m-2·s-1 respectively. Meanwhile, the contents of chlorophyll increase, the proportions of chlorophyll A/B decreased, and the light respiration rate raise, but the dark respiration rate cut down along with the weakening of light intensity of the growing environment. Onelayer shady plants indicate chlorophyll content, biomass, leaf thickness, leaf area, apparent quantum efficiency are biggest. It shows that the suitable light condition of the growth of Tmedia cvHicksii is 50% natural light intensity in the low altitude region of Chongqing.更多还原