铝胁迫下外源钙对外生菌根真菌抗氧化保护酶活性的影响

Effect of Exogenous Calcium on the Activities of Antioxidative Protective Enzymes in Ectomycorrhizal Fungi Under Aluminum Stress

采用液体培养方法,研究了4个不同菌株(Bo 02、Bo 15、Pt 715和Sl 08)的抗铝性及其在铝胁迫下加入0、0.25、0.5、1.0 mmol.-1L-1Ca2+处理后抗氧化保护酶活性的变化,旨在了解钙在缓解外生菌根真菌铝毒方面的作用.结果表明,不同菌株抗铝性不同,Pt 715和Sl 08的抗铝性强于Bo 02和Bo 15.铝胁迫可显著提高外生菌根真菌Bo 02 CAT和SOD活性、Bo 15SOD活性、Sl 08 CAT和POD活性,说明外生菌根真菌中这几种酶活性的提高与铝毒胁迫密切相关.4个菌株中,Bo 02酶活性对外源钙最敏感,外源钙对Bo 02铝胁迫的缓解作用最好.较高浓度的钙(≥0.5 mmol.L-1)可缓解或消除Sl 08铝胁迫造成的抗氧化酶活性上升.

In order to investigate the function of Ca2＋ in the alleviation of Al3＋ stress in ectomycorrhizal fungi,four strains（Bo 02,Bo 15,Pt 715 and Sl 08） were grown in liquid culture media to study the Al resistance of different strains and the effect of exogenous Ca2＋（0,0.25,0.5,1.0 mmol·L-1） on the activity of antioxidative protective enzymes under Al3＋ stress.It was showed that ectomycorrhizal fungal species varied in resistance to Al3＋ stress.Pt 715 and Sl 08 were more tolerant to Al3＋ than Bo 02 and Bo 15 in vitro.The activities of CAT and SOD in Bo 02,SOD in Bo 15,CAT and POD in Sl 08 increased significantly under Al3＋ stress.It was showed that the activities of these enzymes in ectomycorrhizal fungi had a close relationship with Al3＋ stress.The enzymes in Bo 02 were most sensitive to exogenous Ca2＋ and the function of Ca2＋ in resisting Al3＋ stress was the best in the four strains.A high concentration of Ca2＋（≥0.5 mmol·L-1） could alleviate or offset the increased activities of antioxidative protective enzymes by Al3＋ stress in Sl 08.