盐胁迫对8种草本植物幼苗生长和生理特性的影响

Effects of salt stress on growth and physiological characteristics of eight herbaceous plant seedlings

摘要:

为探明盐胁下 8 种草本植物的生长和生理特性，及其 8 种植物耐盐性差异，为兰州新区盐碱地园林绿化提供科学依据，研究了不同浓度 NaCl 处理(0、0. 4%、0. 8%、1. 2%)对 8 种草本植物幼苗生长和生理指标的影响，并利用主成分和综合指标评价方法对其耐盐性进行评价。结果表明：随 NaCl浓度增加，供试植物的根直径、根系活力、叶片相对含水量和叶、根可溶性蛋白含量显著降低；根体积、根表面积、根长、根尖数，叶、根可溶性糖、丙二醛(MDA)含量及超氧化物歧化酶(SOD)活性显著升高；叶绿素 a、叶绿素 b、总叶绿素和叶绿体色素含量先减小后增加；叶、根过氧化物酶(POD)和过氧化氢酶 (CAT)活性先升高后降低，在 NaCl 浓度为 0. 8% 时升至最大。主成分分析和综合指标评价表明，供试植物耐盐性强弱顺序为白三叶＞多年生黑麦草＞高羊茅＞紫羊茅＞波斯菊＞红三叶＞一年生黑麦草 ＞早熟禾。

Abstract:

In order to explore the growth and physiological response of eight herbaceous plants to salt stress and their salt‐tolerance ability，to select landscape plants for saline‐alkali land of Lanzhou New Area，the effects of differ‐ ent concentrations(0，0. 4%，0. 8%，1. 20%)of NaCl stress on seedling growth and physiological indices of eight plant species were studied. The salt‐tolerance abilities of eight plant species were evaluated using the principal com‐ ponent and comprehensive index evaluation method. Results showed that with the increase of NaCl concentration，av‐ erage root diameter，root activity，leaf relative water content and soluble protein content in leaf and in root of the eight plant species decreased gradually. In contrary，root volume，root surface area，root length，root tip number，soluble sugar and MDA contents and SOD activity in leaf and in root increased significantly. Chlorophyll a content，chloro‐ phyll b content，chlorophyll content，and chloroplast pigment content first decreased and then increased significantly. By contrast，POD and CAT activities in leaf and in root first increased and then decreased significantly. The highest increase occurred at 0. 8% concentration of NaCl stress. The results of principal component and comprehensive analysis showed that the order of salt tolerance abilities of the eight plant species were as follows：Trifolium repens＞ Lolium perenne＞Festuca arundinacea＞Festuca rubra＞Cosmos bipinnata＞Trifolium pretense＞Lolium multiflo- rum＞Poa annua.