增强紫外线辐射以及干旱胁迫对滇杨生长及生理影响.pdfVIP

增强的紫外线辐射以及干旱胁迫对滇杨生长及生理的影响 玄祖迎,赵鸿杰,陈 杰,丁岳炼,陈 香 （佛山市林业科学研究所，广东佛山 528222 ） 摘要：本研究在盆栽条件下以滇杨(Populus yunnanensis)为材料，通过研究增强紫外线辐射（UV-B ）和干旱胁 迫单独以及复合作用对滇杨形态和生理生化的影响，探讨了UV-B 对植株抗旱能力的影响。结果表明：UV-B 和干旱胁迫都影响了滇杨的形态生长和生理生化反应；干旱胁迫显著降低了植株叶片数目，增大了根/冠比 (Rs)、细根/总根比(Ft)，提高了超氧化物歧化酶(SOD)的活性；干旱与UV-B 的复合作用加剧了任一单独胁迫 对植株的抑制，表现为更小的株高、基茎、整株叶面积、平均叶面积、总生物量和更高的 MDA 含量，而且 UV-B 辐射降低了干旱胁迫下生物量分配的可塑性，过氧化氢酶(CAT)的活性比任一单独胁迫时都要低。这些 实验结果表明，增强的UV-B 并没有缓解干旱胁迫对植株的伤害作用，反而加剧了对植株的抑制。 关键词：滇杨；紫外辐射；干旱；生长影响；生理响应 The Effect of Supplemental Ultraviolet-B and Drought to the Growth and Physiology of Populus yunnanensis XUAN Zuying, ZHAO Hongjie, CHEN Jie, DING Yuelian, CHEN Xiang (Foshan Institute of Forestry of Guangdong, Foshan, 528222, China) Abstract: Both supplemental UV-B and drought affected the morphological physiological and biochemical responses of P. yunnanensis . Drought decreased the leaf number and increased root/shoot ratio, fine root/total ratio and the activity of superoxide dimutase (SOD). While supplemental UV-B had no effects on these factors. The combination of drought and UV-B augmented the growth inhibition acting as further lower plant height, leaf area biomass and higher MDA. And compared with drought stress, root/shoot ratio and fine root/total root ratio decreased under the combination stresses. Catalase (CAT) activity became lower under combination stresses than that of either stress lonely. According to these results, we suggested that, compared with the effect of stress lonely, the combination of supplemental UV-B and drought did not mitigate the harmful effect, but augmented it. Keywords: Populus yunnanensis, Ultraviolet-B radiation, drought,