以采自陕西杨陵和安塞的2个1年生酸枣幼苗为材料,采用盆栽称重控水法研究了中度和重度土壤干旱胁迫对它们生长和生理特性的影响.结果表明,不同程度的水分胁迫均使2种源酸枣新生侧枝长度受到极显著抑制,其苗高和基径也受到一定程度抑制,同时分别使叶片相对含水量和水分饱和亏有一定程度的降低和升高;2种源酸枣叶片的叶绿素a含量在各水分胁迫均极显著降低,它们的总叶绿素含量也在重度干旱下显著降低;随土壤干旱胁迫时间的延续,2种源酸枣叶片保护酶SOD、CAT、APX活性上下波动,其脯氨酸和可溶性糖含量逐渐升高,而超氧阴离子含量在较低水平下波动,丙二醛含量逐渐降低.杨陵酸枣在土壤水分较好的条件下表现良好,而安塞酸枣则具有更强的适应旱生能力.研究发现,在不同程度的土壤干旱胁迫下,2个种源酸枣的生长均受到一定程度的抑制,但它们均能调节自身的保护酶系统活性和渗透调节物质含量来减轻干旱伤害,维持植物体的正常生理代谢功能,表现出较强的抗旱耐旱能力.%With two provenances of one-year-old wild sour jujube seedlings,named as "SY" form Yangling and "SA" from Ansai in Shaanxi,the effects of water stress on growth and physiological characteristics were studied with controlling water by potted planting.The results showed that water stress decreased the height,basal diameter and newborn lateral branch,and decreased the contents of chlorophyll a (Chl a),chlorophyll b (Chl b) and relative water content (RWC) of leaves on two provenances of seedlings.With the stretch of stress,the activities of protective enzyme,including superoxide dismutase (SOD),catalase (CAT) and ascorbate peroxidase (APX),are in the state of fluctuation,proline and soluble sugar contents increased slowly,which kept superoxide anion (O-·2) down in a low level,and malondialdehyde (MDA) content decreased.The SY seedling showed better under adequate soil water content,and the SA seedling showed better drought-adaptability potential.Both of them were drought-resistant.
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