Rhizobial resource associated with epidemic legumes in Tibet.
A total of 128 bacterial test strains originated from Astragalus, Caragana, Gueldenstaedtia, Medicago, Melilotus, Oxytropis, Trifolium, and Vicia grown in Tibet were characterized phenotypically and genomically. Based upon the consensus of grouping results, they were identified as 16 putative species. Twenty-five test strains belonging to seven putative species of Agrobacterium, Bradyrhizobium, and Rhizobium might be nonsymbiotic bacteria and the remaining 103 test strains were symbiotic bacteria belonging to Mesorhizobium, Rhizobium, and Sinorhizobium meliloti. Although no novel taxon was detected in the symbiotic bacteria, several characters including the alkaliphilic psychrotolerance revealed that the Tibetan rhizobia could be ecotypes adapted to the local conditions. The results also demonstrated that frequent lateral transfer of symbiotic genes might have happened in the Tibetan rhizobia since nodC genes similar to that of S. meliloti were found in several Rhizobium test strains and all the Mesorhizobium species had very similar nodC genes despite their genomic background. All of these findings demonstrated that the Tibetan rhizobia were an important resource for further studies on rhizobial ecology and application.
Key Laboratory of Agro-Microbial Resource and Application, Ministry of Agriculture/College of Biological Sciences, China Agricultural University, 100193, Beijing, China.
Bao Chao
BC
Hou
En Tao
ET
Wang
Ying
Y
Li
Rui Zong
RZ
Jia
Wen Feng
WF
Chen
Chao Xin
CX
Man
Xin Hua
XH
Sui
Wen Xin
WX
Chen
D000217:Acyltransferases / Q000235:genetics; D020561:Alphaproteobacteria / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification* / Q000378:metabolism; D001426:Bacterial Proteins / Q000235:genetics; D004269:DNA, Bacterial / Q000032:analysis; D004275:DNA, Ribosomal / Q000032:analysis; D021903:DNA, Ribosomal Spacer / Q000032:analysis; D007887:Fabaceae / Q000145:classification / Q000382:microbiology*; D017351:N-Acetylglucosaminyltransferases / Q000235:genetics; D009586:Nitrogen Fixation; D010802:Phylogeny; D018517:Plant Roots / Q000382:microbiology*; D016133:Polymerase Chain Reaction / Q000379:methods; D012150:Polymorphism, Restriction Fragment Length; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D015183:Restriction Mapping; D012230:Rhizobiaceae / Q000145:classification / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism; D013559:Symbiosis / Q000235:genetics; D018609:Tibet
D001426:Bacterial Proteins; D004269:DNA, Bacterial; D004275:DNA, Ribosomal; D021903:DNA, Ribosomal Spacer; D012336:RNA, Ribosomal, 16S; D000217:Acyltransferases; C060770:NodA protein, Rhizobiales; D017351:N-Acetylglucosaminyltransferases; C060771:NodC protein, Rhizobiales