紫花苜蓿不同品种对干旱胁迫的生理响应  

A study on physiological responses of varieties of Medicago sativa and their relationship with the drought resistance capacity under drought stress

作　　者：余玲[1] 王彦荣[1] GARNETT Trevor AURICHT Geoff 韩德梁[1] 

机构地区：[1]兰州大学草地农业科技学院,甘肃兰州730020 [2]澳大利亚南澳研究与发展研究所

出　　处：《草业学报》2006年第3期75-85,共11页Acta Prataculturae Sinica

基　　金：ACIAR项目(ASI/1998/026);国家重点基础研究发展规划项目(G2000018602)资助

摘　　要：以国内外20个优良紫花苜蓿品种为材料,研究了离体条件下叶片相对含水量、膜相对透性、游离脯氨酸和叶绿素含量等生理性状对干旱胁迫的响应,探讨了各种生理变化与抗旱性的关系,并结合草产量对其抗旱性进行了综合评价。结果表明,抗旱性强的品种在干旱胁迫下草产量高,叶片保水能力强,叶绿素持有率高,游离脯氨酸维持积累时间较长,维持积累量较高,能保持较高的细胞膜相对完整性。依据上述5项指标,通过系统聚类分析,将20个紫花苜蓿品种分为抗旱性强、较强、中等、较弱和弱5个等级。Four physiological indices including relative water content of leaves, relative permeability of membrance, contents of free proline and chlorophyll were measured under drought stress. Herbage yields under soil drought stress were also measured. Physiological responses were studied and the relation of some physiological changes to drought resistance capacity was evaluated on different varieties of M. sativa and is discussed. The results showed that herbage yields, water-maintaining capacity of leaves, maintenance percentage of chlorophyll and relative integrity of membranes was high. Free proline accumulated for a long time and was maintained at a high level in strong drought resistance varieties under drought stress. Cluster analysis for drought resistance capacity based on herbage yield and the four physiological indices showed that the 20 varieties could be divided into 5 grades of drought resistance capacity： best, good, medium, poor and worst.

关 键 词：紫花苜蓿 草产量 相对含水量 膜相对透性 游离脯氨酸 叶绿素 抗旱性 

分 类 号：S541.9[农业科学—作物学]