太原市五种园林地被植物抗旱性评价及抗旱指标筛选

Drought Resistance Evaluation of Five Plants of Ground Cover in the Garden of Taiyuan and Screening of the Drought-resistance Index

以5种地被植物为试材,采用盆栽控水模拟干旱胁迫(连续干旱0、5、10、15、20 d),分别测定5种地被植物的叶片相对含水量(RWC)、电导率(REC)、丙二醛(MDA)、可溶性蛋白质含量(SPC),并利用隶属函数分析、相关性分析、主成分分析、聚类分析、逐步回归分析对其抗旱性进行综合评价及抗旱指标筛选,以期为太原市园林地被植物的合理养护和筛选应用提供参考依据。结果表明:干旱条件下,不同生理指标所反映供试植物的抗旱性不同,且部分指标之间呈显著相关。主成分分析将12个单项指标归纳成3个综合因子,分别为伤害程度因子、叶绿素因子、水分状况和光化学效率因子,代表了抗旱性97.422%的数据信息,“金冠”玉簪和德国鸢尾分别在3个主因子上抗旱性最强。通过聚类分析,将5种地被植物分为3类,其中“金冠”玉簪、德国鸢尾和八宝景天归为抗旱型类群。逐步回归分析表明,RWC、离体叶片失水速率(RWL)、SPC和PSⅡ最大光化学效率(Fv/Fm)可作为评价参试地被植物抗旱性的重要指标。

The drought resistant capability of five common ground cover plants in the garden of Taiyuan was studied based on the water-controlled pot experiment(continuous drought 0 day,5 days,10 days,15 days,20 days).The relative water content,electrical conductivity,the content of malondialdehyde,soluble protein and other indexes of the tested plants were measured respectively.Subordinate function analysis,correlation analysis,principal component analysis,cluster analysis and stepwise regression analysis were used to evaluate the drought resistance of five ground cover plants and screen drought tolerance index in order to provide reference for the rational maintenance and selection of garden ground cover plants in Taiyuan.The results showed that under the condition of drought stress,the drought resistance coefficients of each index of five ground cover plants were inconsistent,and there was significant correlation between some indexes.Twelve drought-resistance indexes could be classified into three component parts by principal components analysis based on subordinate function value,extent of injury factor,chlorophyll factor,photochemical efficiency and water status factor.Three principal factors presented 97.422% of the information of the 12 indexes.Iris germanica and Hosta plantaginea ‘Golden Tiara’ had the strongest drought-resistance for the three principal factors,respectively.According to the clustering analysis,the five ground cover plants could be clustered into three groups,and Hosta plantaginea ‘Golden Tiara’,Iris germanica and Sedum spectabile belonged to the strong drought-resistance group.Combined with stepwise regression analysis,leaf water loss rate,relative water content,soluble protein content and maximum quantum yield of PSⅡ could be used as important indexes to evaluate the drought resistance of tested ground cover plants.