干旱胁迫及复水对6种园林灌木生理特性的影响

Effects of drought stress and rewatering on physiological response of six shrub species

以花叶鹅掌柴、龙船花、白蟾、狗牙花、软枝黄蝉和红背桂6种园林灌木为材料,研究人工模拟干旱胁迫环境对植物幼苗叶片生理指标的影响,并结合主成分分析综合评价6种灌木的抗旱能力强弱。结果表明,干旱胁迫能显著降低6种灌木的叶片组织含水量,复水4 d后,花叶鹅掌柴、龙船花和红背桂叶片组织含水量恢复至对照水平;干旱胁迫期间叶绿素、脯氨酸、可溶性蛋白、丙二醛(MDA)含量,叶片相对电导率和超氧化物歧化酶(SOD)活性增加或显著增加。复水后,狗牙花、软枝黄蝉和红背桂的叶绿素含量,白蟾和狗牙花的可溶性蛋白含量,狗牙花的脯氨酸含量,龙船花的MDA含量均恢复至对照水平;除了花叶鹅掌柴,其余5种植物可溶性糖含量也恢复至对照水平;花叶鹅掌柴的相对电导率,白蟾、狗牙花和红背桂的相对电导率和SOD活性也恢复至对照水平。主成分分析结果表明,6种园林灌木的抗旱性表现为花叶鹅掌柴>狗牙花>红背桂>软枝黄蝉>白蟾>龙船花。

The physiological changes of Schefflera odorata cv.Variegata,Ixora chinensis,Gardenia jasminoides var.fortuniana,Ervatamia divaricata,Allemanda cathartica and Excoecaria cochinchinensis were studied under drought stress and rewatering in a greenhouse.This study also evaluated their drought resistance through physiological parameters and principal components analysis.The results showed that the leaf water content of these seedlings decreased during drought stress and S.odorata cv.Variegata,I.chinensis and E.cochinchinensis returned to the controls level after rewatering.The chlorophyll content,proline content,soluble protein content,soluble sugar content,MDA contents,relative conductivity and SOD activity increased or significantly increased during drought period.After rewatering,the chlorophyll content of E.divaricata,A.cathartica and E.cochinchinensis,protein content of E.divaricata,MDA contents of I.chinensis recovered to the control level.The soluble sugar content of most species restore to the status of the controls except S.odorata cv.Variegata.The relative conductivity of S.odorata cv.Variegata,relative conductivity and SOD activity of G.jasminoides var.Fortuniana,E.divaricata and E.cochinchinensis recovered to the control level.Seedlings’physiological properties were evaluated using principal component analysis,and their ability of drought resistance was sequenced as S.odorata cv.Variegata>E.divaricata>E.cochinchinensis>A.cathartica>G.jasminoides var.fortuniana>I.chinensis.