干旱胁迫对空心莲子草抗氧化酶活性和组织学的影响

目的:空心莲子草是一种水旱两栖植物,对其抗旱性的研究越来越受到重视。初步探讨空心莲子草的抗旱机理,为进一步的分子生物学实验奠定基础。方法:采用干旱胁迫的方法,测定空心莲子草的根和叶中抗氧化酶类(SOD、POD、CAT等)的活性变化,并对其组织学的变化进行分析比较。结果:在干旱胁迫下,空心莲子草总抗氧化能力一直增大,抗氧化酶活性是先增大后减小。干旱胁迫下根中抗氧化酶的活性比叶中的活性要高,总抗氧化能力也较强。经组织学比较发现,干旱胁迫后根和叶的组织细胞变小,并有少量细胞坏死。结论:空心莲子草具有较强的抗旱性,表现在干旱胁迫时根和叶能合成大量的抗氧化酶以抵抗干旱胁迫给机体带来的伤害作用,并且总抗氧化能力一直处于较高的水平。

Effects of Drought Stress on the Activities of Anti-Oxidant Enzymes and Histology in Alternanthera philoxeroides

Objective: Alternanthera philoxeroides is one of the amphibious plants that can normally grow both in water and on earth.People are attaching more importance to its drought-resistance.To study the mechanism of drought-resistance and establish the foundation for the further molecular biology experiment.Methods: A.philoxeroides were treated with drought stress.The activities of anti-oxidant enzymes(SOD,POD,CAT,etc) and the changing of histological structure on the leaves and roots in A.philoxeroides were studied.Results: Results showed that the total anti-oxidant capacity of A.philoxeroides increase and the activities of anti-oxidant enzymes to reduce after increasing under the drought stress.The comparison of them in roots and leaves revealed that,as to anti-oxidant enzymes,the contents of them in leaves were the stronger than that in roots,and as for total anti-oxidant capacity,it was as same as that of anti-oxidant enzymes.Their cells in the leaves and roots changed small and necrotic cells were present used the histology method.Conclusion: A.philoxeroides has stronger drought-resistance.Its roots and leaves can synthesize large quantities of anti-oxidant enzymes by resisting the injury under the drought stress,and total anti-oxidant capacity has been in higher level all the time.