丛枝菌根真菌对盐(碱)-旱交叉胁迫下羊草幼苗生长与抗氧化酶活性的影响

Effects of Arbuscular Mycorrhizal Fungi on Growth and Antioxidant Enzyme Activities of Leymus chinensis Seedlings Under Salt (Alkali) and Drought Stress

羊草营养价值丰富、抗逆性强,是东北松嫩平原最重要的牧草之一。丛枝菌根真菌(AMF)能与绝大多数陆地植物共生,且影响其抗逆性。本文对羊草幼苗接种丛枝菌根真菌并采用NaCl、NaHCO3以及PEG来模拟不同盐(碱)-干旱胁迫条件,研究逆境交叉胁迫下共生体生长与抗氧化酶活性的变化。结果表明,在盐(碱)胁迫与干旱胁迫以及盐-旱与碱-旱交叉胁迫下,丛枝菌根真菌均一定程度提高了羊草幼苗的生物量,碱-旱互作的胁迫效应远大于盐-旱互作。盐碱和干旱胁迫下,SOD、POD和APX活性均升高,而CAT的活性则呈下降趋势,接种丛枝菌根真菌后,交叉胁迫下抗氧化酶活性同样呈上升趋势。研究结果对于深入理解羊草逆境交叉胁迫适应机理以及丛枝菌根真菌生理功能等科学问题提供了一定理论依据。

Leymus chinensis is one of the most important forages in the Songnen Plain of Northeast China because of its rich nutritional value and strong stress resistance.Arbuscular mycorrhizal fungi (AMF)can coexist with a large number of terrestrial plants and affect their stress resistance.In this paper, AMF was inoculated into Leymus chinensis seed lings, the changes of symbiotic growth and antioxidant enzyme activities under cross stress were studied by using NaCl,NaHCO3 and PEG to simulate different types of salt(alkali)-drought stress conditions.The results showed that AMF increased the biomass of Leymus chinensis seedlings to a certain extent under salt (alkali) stress and drought stress, as well as salt-drought and alkali-drought cross-stress.The stress effect of alkali-drought interaction was much greater than that of salt-drought interaction.Under saline-alkali and drought stress,the activities of SOD,POD and APX increased,while the activities of CAT decreased.After inoculating with AMF,the activities of antioxidant enzymes also increased under cross-stress.The research results provide a theoretical basis for understanding the adaptation mechanism of the cross-stress and the physiological functions of AMF.