%0 Journal Article
%A 2
%A BAI Kun-Dong2*
%A GUO Chuan-You1
%A JIANG De-Bing3
%A ZHANG Qiang1
%A ZHANG Xing-Wang1
%T Photosynthesis and Antioxidant Defense Strategies in Overwintering Plants of <em>Tsuga chinensis</em> and <em>Cyclobalanopsis stewardiana</em>
%D 2015
%R 10.7525/j.issn.1673-5102.2015.02.007
%J Bulletin of Botanical Research
%P 200-207
%V 35
%N 2
%X We selected two dominant tree species including <em>Tsuga chinensis</em> and <em>Cyclobalanopsis stewardiana</em> grown in the evergreen needle-leaved and broadleaved mixed forest at high-altitude on Mao&rsquo;er Mountain, and studied their seasonal changes in photosynthetic pigments, net photosynthetic rate(<em>A</em><sub>max</sub>), chlorophyll fluorescence and antioxidative system. <em>T.chinensis</em> and <em>C.stewardiana</em> down-regulated the values of chlorophyll(Chl) content, predawn maximum photochemistry efficiency of PSⅡ(<em>F</em><sub>v</sub>/<em>F</em><sub>m-predawn</sub>), <em>A</em><sub>max</sub> and stomatal conductance(<em>G</em><sub>s</sub>) to the minimum during winter stress. The activities of superoxide dismutase(SOD), peroxidase(POD), catalase(CAT) and the contents of ascorbic acid(AsA), glutathione(GSH) and carotenoids(Car) of <em>C.stewardiana</em> were the highest in winter, which showed good synergy in resisting adverse external environments and scavenging reactive oxygen species(ROS), while only AsA, GSH and Car in <em>T.chinensis</em> maintained good synergy in resisting winter stress. The seasonal changes of MDA contents in <em>T.chinensis</em> and <em>C.stewardiana</em> were correlated with the seasonal variations of environment as well as the seasonal variations of antioxidative enzyme activities and antioxidants accumulation. Therefore, <em>T.chinensis</em> and <em>C.stewardiana</em> had different antioxidant-defense strategies, but the same photosynthetic adaptation strategy was down regulation for winter acclimation.
%U https://bbr.nefu.edu.cn/EN/10.7525/j.issn.1673-5102.2015.02.007