杨桐幼苗对干旱胁迫的生理响应

为探明杨桐幼苗对持续干旱胁迫的适应能力,以1年生杨桐为材料,通过盆栽模拟干旱环境,研究不同干旱胁迫程度对杨桐幼苗叶片生理生化特性的影响。结果表明:在干旱胁迫下,杨桐叶片相对含水量和自由水含量呈下降趋势,束缚水、可溶性糖和游离脯氨酸含量呈上升趋势;可溶性糖和游离脯氨酸含量与叶片相对含水量呈显著负相关,与束缚水的含量呈显著正相关;重度干旱胁迫,丙二醛含量显著提高,导致膜损伤,质膜透性上升;超氧化物歧化酶和过氧化物酶活性呈先升后降。对相对含水量、自由水含量等9个抗旱指标进行主成分分析发现,前2个主成分的累计贡献率达95.61%。

Physiological Responses of Adinandra millettii Seedlings to Drought Stress

In order to explore the adaptability of A.millettii seedlings to continuous drought stress, taking 1-year A.millettii seedlings as the materials, a pot experiment was conducted to explore the effects of drought stress in varying degrees on physiological and biochemical characteristics of A.millettii seedling leaves.Results: Under drought stress the relative water content and free water content decreased, while contents of bound water, soluble sugar and proline increased;Contents of soluble sugar and proline negatively correlated with relative water content in leaves, and significantly positively correlated with bound water content;Under severe drought stress, MDA content significantly increased, which led to membrane damage, and permeability of membrane rise;activities of SOD and POD increased first and then decreased.Through the principal component analysis of nine indicators, it is found that accumulative contribution rate of the first two indicators is up to 95.61%.