茅苍术叶片可培养内生细菌多样性及其促生潜力  

Diversity and plant growth-promoting potential of culturable endophytic bacteria isolated from the leaves of Atractylodes lancea

作　　者：周佳宇[1] 贾永[1] 王宏伟[1] 戴传超[1] 

机构地区：[1]南京师范大学生命科学学院、江苏省微生物与功能基因组学重点实验室、江苏省微生物资源产业化工程技术研究中心,南京210023

出　　处：《生态学报》2013年第4期1106-1117,共12页Acta Ecologica Sinica

基　　金：国家自然科学基金项目(31070443,30970523);江苏高校优势学科建设工程资助项目;江苏省工程中心创新能力提升项目;江苏省教育厅产业化推进项目(JHB2012-16);南京市科委工程中心创新能力提升项目(201105058)

摘　　要：对江苏省道地药材茅苍术叶片可培养内生细菌的多样性及其固氮、解磷、解钾、产生长素的能力进行研究。依据菌落形态的不同,共分离得到52株内生细菌。能正常传代培养的45株内生细菌经ARDRA分析后归入14个聚类簇,簇内菌株的BOX-PCR指纹图谱相似度不高,在属水平上显示出茅苍术内生细菌丰富的多样性。各聚类簇代表菌株16S rDNA的序列分析表明分离得到的内生细菌与泛菌属、微杆菌属、短杆菌属、农杆菌属、假单胞菌属、芽孢杆菌属细菌亲缘关系相近,优势内生细菌与假单胞菌属细菌亲缘关系相近。45株能正常传代培养的内生细菌中,有10株能够在无氮培养基上正常生长,具固氮潜力。使用nifH基因通用引物对其基因组进行扩增后,除ALEB 33外,其它9株内生细菌均可获得与nifH基因片段大小相近的条带。分别使用NBRIP培养基和蒙金娜有机磷培养基筛选后获得19株和15株能够溶解磷酸钙和卵磷脂的内生细菌,其中ALEB 43溶解无机磷的能力最强,达(251.43±6.55)mg/L;ALEB 4A溶解有机磷的能力最强,达(23.63±1.46)mg/L。部分内生细菌溶解无机磷的能力与其产酸能力呈正相关,而菌株溶解有机磷的能力却无此相关性。通过硅酸盐培养基的筛选,获得具有解钾潜力的菌株24株。43株内生细菌能够将色氨酸转化为生长素,其中ALEB 44产生长素的能力最强,达(268.44±10.12)μg/mL。本研究首次揭示了江苏省道地药材茅苍术体内丰富的内生细菌资源及其促生长潜力,对进一步阐述茅苍术与内生菌之间的相互关系具有重要意义。Atractylodes lancea is a medicinal plant grown in Jiangsu Province,China.The diversity of the endophytic bacteria culturable from the leaves of A.lancea and their plant growth-promoting potential,including nitrogen fixation,phosphorus solubilization,potassium solubilization and indole acetic acid（IAA） production were investigated.According to morphological characteristics of bacterial colonies,52 endophytic bacterial strains were obtained and 45 could be subcultured normally in vitro and subjected to amplified ribosomal DNA restriction analysis（ARDRA）.Based on the ARDRA fingerprints,the 45 subculturable endophytic bacterial strains could be classified into 14 clusters.The 16S rDNA fragments of representative strains from different clusters were sequenced and deduced by a BLAST search to identify similar strains.The results showed that the isolated endophytic bacteria most likely belong to Pantoea sp.,Microbacterium sp.,Curtobacterium sp.,Agrobacterium sp.,Pseudomonas sp.,or Bacillus sp.Among them,the Pseudomonas sp.was the most dominant genera.BOX-PCR was then used to study the diversity of the endophytic bacteria in the main ARDRA clusters.The BOX-PCR fingerprints showed that the endophytic bacteria in the same cluster were not similar,indicating a broad genetic diversity within the same genera.Ten of the 45 subculturable endophytic bacteria could grow normally on Burk′s medium,which indicates their potential to fix nitrogen.We also amplified the nifH genes in these strains and all strains generated a band of the expected size except for ALEB 33.Among all subculturable endophytic bacteria,19 and 15 strains could dissolve insoluble calcium phosphate and lecithin,respectively,and then release dissociative phosphorus into the medium.ALEB 43 could dissolve the largest amount of phosphorous from calcium phosphate,reaching（251.43±6.55） mg/L.Furthermore,ALEB 4A could dissolve the largest amount of phosphorous from lecithin,reaching（23.63±1.46） mg/L.After comparing the amount of phosphorous dissolved

关 键 词：茅苍术 内生细菌 多样性 促生潜力 

分 类 号：S567.211[农业科学—中草药栽培]