【摘要】 以不同光强下的3年生曼地亚红豆杉(Taxusmediacv.Hicksii)为材料,并以自然光作为对照,探讨了光强对曼地亚红豆杉膜代谢及体内保护系统的影响,结果表明:一层遮荫较对照提高了保护酶SOD、POD、CAT活性和抗氧化物质ASA(ascorbicacid抗坏血酸)的含量,降低了O2.-产生速率、MDA(malondialdehyde丙二醛)含量和细胞膜相对透性,从而使膜脂过氧化维持在一定水平。而二层遮荫下的叶片CAT活性较对照明显增强,但由于SOD、POD酶活性及ASA含量均较对照降低,而使O2.-产生速率、MDA含量上升,细胞膜相对透性有所增加。结果表明,一层遮荫(50.0%的透光率)提高了曼地亚红豆杉清除活性氧的能力,是曼地亚红豆杉在重庆低海拔地区种植的最适宜的光环境。更多还原

【Abstract】 The effects of light intensity on metabolizing of membrane and inner protective system of 3-year-old Taxus media cv.Hicksii leaves grown at different light intensity are studied. The results show that one-layer shade increases the activity of protective enzyme such as POD,SOD and CAT and the content of antioxidative material, but decreases O2.- production rate, MDA’content and the permeability of relative embrane ,thus can keep the level of membrane lipid peroxidation at the fixed standard. However, under two-layer shade, O2.- production rate , MDA’s content and the permeability of relative embrane are increased because of decreasing of SOD ,POD activities and ASA’s content in spite of the increasing of CAT activity. Thus it could be seen that one-layer shade (50.0% of full sunlight ) raised the ability of scavenging free radical and that it is the most suitable environment planted in the low elevation district in Chongqing.更多还原