不同种源单叶蔓荆对干旱胁迫的生理响应与耐旱性评价

Physiological Response of Vitex trifolia var. simplicifolia from Different Provenances Under Drought Stress and Evaluation of Drought Tolerance

以19个不同种源单叶蔓荆当年生扦插苗为试材,在75%～80%(CK)、35%～40%(轻度干旱)、15%～20%(重度干旱)不同水分梯度下,研究不同干旱处理对单叶蔓荆叶片过氧化氢酶(CAT)、超氧化物歧化酶(SOD)、过氧化物酶(POD)活性,脯氨酸(Pro)、可溶性糖(SS)、可溶性蛋白(SP)、丙二醛(MDA)含量和枝条、叶面积增长量等生理生化及形态指标的影响。结果表明:随干旱胁迫程度加大,枝条、叶面积增长量降低;多数种源单叶蔓荆叶片CAT、SOD活性降低,POD活性升高;Pro、SP、MDA含量升高,SS含量呈不同的变化趋势。各指标变化趋势因种源不同而异,干旱胁迫对单叶蔓荆生理生化及形态指标均具有显著影响,且种源间差异显著。用聚类分析法将19个不同种源的单叶蔓荆耐旱性分为强、中、弱3类,采用隶属函数法加权重定量鉴定19个不同种源单叶蔓荆耐旱性,其中抗旱最强的有荣成(D19)、日照(D11)、幸福林场(D13),最弱的有大窑(D8)、大连(D15)、象山(D12)。

Using cutting seedlings of Vitex trifolia var.simplicifolia from 19 different provenances as test materials,this research investigated the physiological and morphological indices of leaf protective enzymes(CAT,SOD,POD),proline,soluble sugar,soluble protein,malondialdehyde(MDA)content,and the growth of branch and leaf area under different water gradient conditions(75%-80%,35%-40%,15%-20%).The results showed that when the drought stress increased,the growth of branch and leaf area decreased;the activity of CAT and SOD from most of the provenances decreased;the activity of POD increased;the content of proline,soluble protein and MDA increased,and the content of soluble sugar showed different trend.The variation trend of each index varied with different provenance,and drought stress had significant influence on the physiological and morphological indices of V.trifolia var.simplicifolia,with significant difference between provenances.Using the method of clusteranalysis,seedlings of V.trifolia var.simplicifolia from the 19 different provenances were divided into 3 categories of strong,medium and weak for drought resistance.Investigation of more accurate identification and comparison for drought resistance of the 19 different provenances were carried out using subordinate function values analysis.The results showed that the highest drought resistance of the 19 different provenances were:Rongcheng(D19)、Rizhao(D11)、Xingfulinchang(D13),and the most drought sensitive provenances were Dayao(D8)、Dalian(D15)、Xiangshan(D12).