PEG胁迫对不同地理种源沙拐枣生理特性的影响

以甘肃省不同地理种源沙拐枣幼苗为试材,采用PEG-6000模拟胁迫方法,研究不同浓度的PEG胁迫处理对沙拐枣幼苗生理特性的影响。结果表明,不同地理种源沙拐枣幼苗的脯氨酸(Pro)含量随胁迫时间的延长而不断增加,可溶性糖含量随时间的延长呈先上升后下降再上升的趋势,丙二醛(MDA)含量随着处理时间延长呈先上升后降低的趋势,超氧化物岐化酶(SOD)活性随时间的延长出现了“M”型的变化趋势,过氧化物酶(POD)活性均是先升高后降低的趋势。3个地理种源幼苗在不同强度PEG胁迫处理下总体变化趋势基本一致,而各胁迫处理间差异显著(P<0.05),脯氨酸含量增加幅度为武威>酒泉>张掖。可溶性糖含量增加幅度为酒泉>张掖>武威。MDA含量增加幅度为武威>张掖>酒泉。SOD活性增加幅度为武威>张掖>酒泉,而POD活性的增加幅度则是酒泉>武威>张掖。不同地理种源沙拐枣的耐旱机制存在差异,而保护酶系统的调节是其对生态环境适应的重要生理反应。

Effects of PEG stress on physiological characteristics of Calligonum mongolicum in different geographical provenance

To simulate the solution drought stress condition with different concentrations PEG-6000,we studied the effects of drought-resistant of physiological characteristics in Calligonum mongolicum seedlings from different geographical provenance in Gansu province.The results indicated that content of Pro increased with the stress time prolong,content of SS(soluble sugar) raised first,then declined,and increased continually later,content of MDA(malondehyde) increased first and then decreased,SOD(superoxide dismutase) activity presented "M" tendency,POD(peroxide enzyme) activity increased first and then decreased.The seedlings of three geographical provenances generally presented a similar tendency under different concentrations and long-term stress while with the significant difference(P<0.05).The increasing range of Pro content was Wuwei>Jiuquan>Zhangye,soluble sugar content was Jiuquan>Zhangye>Wuwei,MDA content was Wuwei>Zhangye>Jiuquan,SOD activity was Wuwei>Zhangye>Jiuquan,POD activity was Jiuquan>Wuwei>Zhangye.There existed difference of drought resistance mechanism of C.mongolicum,but the adjustment of protection enzymes was an important physiological reaction to the environment adaptability.