Isolation and characterization of rhizobia from nodules of in Thailand.

Rhizobia were isolated from the root nodules of in Thailand. The phylogeny of the isolates was investigated using 16S rDNA and the internal transcribed spacer (ITS) region from 16S to 23S rDNA. The phylogenetic tree of the 16S rDNA showed that ten of the eleven isolates belonged to , and one belonged to . The topology of the ITS tree was similar to that of 16S rDNA. The acetylene reduction activity was higher for the nodules inoculated with the isolated strains than for those inoculated with strains. When plants were inoculated with various USDA strains isolated from , formed many effective nodules with , especially USDA61. However, acetylene reduction activity per plant and the growth were higher in inoculated with our isolates. From these data we propose that effective rhizobia inoculant were identified for cultivation.