外生菌根提高植物抗铝性机理研究进展

Mechanism on Increasing Plant Aluminium Resistance by Ectomycorrhizae

外生菌根真菌是土壤中一类重要的微生物,能与70%￣75%的森林树种形成外生菌根。它可以促进植物对养分的吸收和利用,提高酸性土壤上植物的抗铝性。外生菌根主要通过以下几方面来增强植物的抗铝能力:(1)扩大吸收面积,增加植物对养分的吸收;(2)排斥或吸附铝离子,阻止其向植物根系运输;(3)有机酸或其它有机物质的分泌增加,提高对铝离子的螯合和对钙、镁等离子的溶解能力;(4)增加激素的分泌,促进植物生长;(5)促进植物生长稀释铝和液泡区域化隔离铝。

Ectomycorrhizal fungi, a group of important microorganism in soil which can form symbiont with 70%-75% of the forest trees, could enhance plant＇s ability of absorbing and utilizing of nutrient and of tolerating to Al. The mechanism on improving plant aluminium resistance by ectomycorrhizae showed as follows： （1） enhanced plant＇s ability of absorbing of nutrient by hyphae; （2） prevented aluminium from transporting to roots by excluding or adsorbing by ectomycorrhizal fungi; （3） improved the ability to chelate Al or dissolve Ca and Mg by increasing exudation of organic acids or other substances; （4） promoted hormone exudation; （5） diluted Al concentration in plant by promoting plant growth and isolated Al in vacuole.