豆科植物根瘤中非共生的内生菌遗传多样性研究进展

在豆科植物与根瘤菌之间结合形成的固氮共生体中,其典型的特征是由特定的微共生体诱导形成的根瘤或茎瘤,除了根瘤菌外,在根瘤中同样也分离出多种与根瘤菌共生固氮无关的内生菌类群,而且根瘤菌与内生菌通常可以共存于同一个根瘤内是普遍存在的客观现象,这些非共生的内生菌生活史的一部分存在于根瘤内且不会引起植物发病,但有关它们的生态学作用还知之甚少,由于其生态上的重要性,近年来对该现象的研究不断深入.就近年来根瘤中隶属于变形菌门,放线菌门、后壁菌门的非共生的内生菌遗传多样性所取得的最新研究结果进行了总结,并介绍了根瘤中相关内生菌多样性研究的新进展.同时,指出了该研究领域存在的问题,并对未来相关研究方向做了展望.

Genetic Diversity of Nonsymbiosis Endophytic Bacteria in Leguminous Root Nodules

During the synaptic formation of nitrogen-fixing symbiont between legumes and rhizobia,the typical feature is the formation of root nodules and/or stem nodules induced by specific microsymbiont,except for rhizobia,inside the root nodules there are various endogenous microbes(EM) that have no relation to rhizobial symbiotic nitrogen fixation been isolated,and the general coexistence of rhizobia with nonsymbiotic EM in the same root nodule is ubiquitously objective phenomena.Part of life cycle of these nonsymbiotic EM existed in the root nodules were not able to induce the plants into morbidity.However,very little of their ecological role have been aware of.Recently the study on these phenomena has been continuously deepened because of their ecological importance.The updated outcomes of study on endogenous genetic diversities of nonsymbiotic microbes belonged to the phylum of Proteus,Actinobacteria,and Firmicutes in the root nodules were summarized in this paper as well as the new study advancement of diversity of nonsymbiotic microbes in the root nodules was introduced.Furthermore,some questions existed in the field was also put forward,and prospect on the related study was forecasted.