5种杜鹃对干旱胁迫的生理响应及抗旱性评价

Physiological Response to Drought Stress and Drought Resistance Evaluation of Five Azalea Varieties

以4种芳香杜鹃为试验材料,胭脂蜜为对照品种。研究了不同程度干旱胁迫对杜鹃叶片形态、生理指标的影响;应用隶属函数法对5种杜鹃的抗旱性进行了评价,以筛选抗旱性强的芳香杜鹃品种并为今后推广应用和新品种选育提供参考依据。结果表明:干旱胁迫30 d后,5种杜鹃叶片相对电导率以胭脂蜜最高,刺毛杜鹃最低;可溶性蛋白质含量、可溶性糖含量、游离脯氨酸含量、丙二醛含量均随干旱胁迫程度的加剧而不断增加;可溶性蛋白质含量和游离脯氨酸含量均以刺毛杜鹃最高,胭脂蜜最低;可溶性糖含量则以岭南杜鹃最高,马银花最低;丙二醛含量则以马银花最高,刺毛杜鹃最低。所有杜鹃的超氧化物歧化酶和过氧化氢酶活性在干旱胁迫前期均大幅上升,而后期则有所下降,干旱胁迫30 d后的酶活性均以岭南杜鹃最高,胭脂蜜最低。由此可知,5种杜鹃抗旱性强弱排序为:刺毛杜鹃>岭南杜鹃>麂角杜鹃>马银花>胭脂蜜。

Four aromatic azalea varieties were used as test materials,and Yanzhimi was used as control variety.The effects of drought stress on leaf morphology and physiological indexes were studied.The effects of drought resistance were evaluated by membership function method,in order to screen strong drought resistance and provide reference for future application and breeding of new varieties.The results showed that the relative conductivity of the five azalea leaves was the highest in Yanzhimi and the lowest in R.championiae after 30-day stress.However,the content of soluble protein,soluble sugar,free proline and MDA all increased with the aggravation of the stress degree.The content of soluble protein and free proline was the highest in R.championiae and the lowest in Yanzhimi.For the content of soluble sugar,R.mariae was the highest,and R.ovatum was the lowest.The content of MDA was the lowest in R.championiae and the highest in R.ovatum.The SOD and CAT activities of all azalea varieties increased significantly at the early stage of stress,but decreased at the later stage.The activity after 30 days of stress was the highest in R.mariae and the lowest in Yanzhimi.The strength of drought resistance of five azalea varieties was ranked as:R.championiae>R.mariae>R.latoucheae>R.ovatum>Yanzhimi.