干旱胁迫对北美丁香生长和部分抗旱生理生化指标的影响

Effect of Drought Stress on Growth and Drought-resistant Physiological Index of North America Syringa vulgaris L.Seedlings

以2年生北美丁香"詹姆斯"为试材,用盆栽方法人工模拟土壤干旱胁迫条件,研究了其生长和部分抗旱生理生化指标对水分胁迫的响应。结果表明:丁香苗具有一定的抗旱耐旱潜力,当遭遇干旱胁迫时,其可以通过调节自身的渗透调节物质含量和保护酶活性来减轻干旱伤害。随着干旱胁迫加剧,丁香苗植株高度和茎基生长速率逐渐降低,在重度干旱胁迫下生长几乎停止;随着干旱胁迫强度的增加,其叶片叶绿素和相对含水率(RWC)含量逐渐降低;叶片相对电导率、丙二醛(MDA)和脯氨酸(Pro)含量呈现不断增多的趋势;超氧化物歧化酶(SOD)、过氧化氢酶(CAT)和过氧化物酶(POD)活性先升高后降低,在干旱胁迫40d时活性达到最高,在干旱胁迫50d后其含量不断降低。

Two-year-old seedlings of North America Syringa vulgaris L. ＇James＇ were used to study the effects of drought stress on growth and partical drought-resistant physiological and biochemistry indexes,which were controlled by pot plant to simulate soil drought stress. The results indicated that the North America Syringa vulgaris L. ＇James＇ had the certain potential of resistance to drought tolerance,and osmotic adjustment substance and the antioxidant enzyme activities content increased significantly under drought stress of Syringa vulgaris L. to relieve the damage from the soil drought stress. With the intensity of drought stress increasing, the growth of the Syringa vulgaris L. seedlings height and its stem bottom gradually decreased,and they almost stopped growing under severe drought stress. As drought stress was intensified, leaf chlorophyll and the relative water content gradually decreased. And the leaf electrical conductivity, the MDA and Pro contents increased little by little ~ while the SOD,CAT and POD activity rised at first and went down latter. The activities of the SOD, CAT and POD reached the maximum on the 40th day and dropped gradually after 50 days of soil drought stress.