盐碱胁迫对刺槐和绒毛白蜡叶片叶绿素含量的影响

Effect of Salt-Alkalic Stress on Content of Chlorophyll in Leaves of Robinia pseudoacacia and Fraxinus velutina Seeding

用不同浓度的中性盐(NaCl)和碱性盐(NaCl、NaHCO3、Na2SO4、Na2CO3)溶液处理1 a生刺槐和绒毛白蜡,研究了两树种叶片中叶绿素a、叶绿素b和总叶绿素含量的动态变化以及叶绿素和丙二醛、脯氨酸的相关性。结果表明:在中性盐的胁迫下,刺槐和绒毛白蜡总叶绿素和叶绿素a的含量随盐胁迫程度的增加而降低,叶绿素b的变化较小,叶绿素a/b并不呈现单一的变化趋势;在碱性盐的胁迫下,刺槐总叶绿素和叶绿素a的含量随胁迫程度的增加呈现先升高后降低再升高的趋势,绒毛白蜡总叶绿素和叶绿素a的含量随胁迫程度的增加而上升,叶绿素b的变化较小,叶绿素a/b都呈现上升的趋势。相关分析表明,两树种在中性盐和碱性盐胁迫下,总叶绿素含量与膜脂过氧化产物丙二醛含量呈负相关;中性盐胁迫下,刺槐和绒毛白蜡都与脯氨酸呈正相关。

One-year -old poted Fraxinus velutina and Robinia pseudoacacia seedings were tested by neutral salt and mixed salt solutions. The dynamic changes of a, b and total contents of chlorophyll were studied and the correlation of chlorophyll with MDA and Pro was analysed. The results showed that both of the chlorophyll a and total chlorophyll contents decreased under the stress of neutral salt. The changes of the chlorophyll b was not obvious and a/b not consistent. The chlorophyll a and total chlorophyll of R. pseudoacacia appeared an increasing- declining-increasing trend under the stress of mixed salt. The chlorophyll a and total chlorophyll of F. velutina increased under the stress of mixed salt. The changes of the chlorophyll b was not obvious either and a/b appeared a rising trend. Correlation analysis indicated that total chlorophyll contents in leaves of F. velutina and R. pseudoacacia Seedlings were negatively correlated with MDA content under both neutral salt stress and mixed salt stress. The total chlorophyll contents was positively correlated with Pro under neutral salt stress. However, the correlation was negative under mixed salt stress.