干旱胁迫下委陵菜和翻白委陵菜叶片结构和生理指标的变化

以委陵菜（Potentilla chinensis）和翻白委陵菜（P.discolor）为试验材料，研究土壤干旱胁迫条件下植物叶片解剖结构和生理指标的变化。结果表明，随着干旱胁迫的增强，两种植物栅栏组织和海绵组织厚度变化较明显，翻白委陵菜的栅栏组织与海绵组织比值较委陵菜大；两种植物叶绿素含量均逐渐下降，超氧化物歧化酶（SOD）活性均呈先上升后下降的趋势，丙二醛（MDA）和脯氨酸含量都逐渐增加。比较两种植物各项指标的变化幅度，发现翻白委陵菜适应干旱的能力较委陵菜强。因此，叶片解剖结构和各项生理指标的变化可以作为评价两种委陵菜属植物对干旱胁迫敏感度的指标之一。

Effects of drought stress on anatomical structure of leavesand physiological indexes of Potentilla species

Potentilla chinensis and P.discolor were taken as experimental materials to study their anatomical structures and physiological indexes under drought stress. The results showed that with the drought stress strengthened, the thickness of palisade tissue and spongy parenchyma changed obvious, P.discolor was greater than P.chinensis on the ratio of palisade tissue and spongy parenchyma, the chlorophyll content decreased gradually, the SOD activity increased first and then showed a downward trend, the MDA and PRO content gradually increased. Through the comparison of two kinds of plants on the changes in amplitude of indicators, it could be concluded that the ability of drought stress of P.discolor was stronger than P.chinensis. The anatomical structure of leaves and the change of physiological indexes change under drought stress could be used to evaluate the sensitivity of drought stress of plants of genus Potentilla.