Phenotypic and genotypic diversity of root nodule bacteria from wild Lathyrus and Vicia species in Gaziantep, Turkey.

Abstract

This study identified the phenotypic and genotypic characteristics of the bacteria that nodulate wild Lathyrus and Vicia species natural distribution in the Gaziantep province of Turkey. Principle component analysis of phenotypic features revealed that rhizobial isolates were highly resistant to stress factors such as high salt, pH and temperature. They were found to be highly sensitive to the concentrations (mg/mL) of the antibiotics neomycin 10, kanamycin, and tetracycline 5, as well as the heavy metals Ni 10, and Cu 10, and 5. As a result of REP-PCR analysis, it was determined that the rhizobial isolates were quite diverse, and 5 main groups and many subgroups being found. All of the isolates nodulating wild Vicia species were found to be related to Rhizobium sp., and these isolates were found to be in Clades II, III, IV, and V of the phylogenetic tree based on 16S rRNA. The isolates that nodulated wild Lathyrus species were in Clades I, II, IV, V, VI, VII, and VIII, and they were closely related to Rhizobium leguminasorum, Rhizobium sp., Phyllobacterium sp., Serratia sp., and Pseudomonas sp. According to the genetic analyses, the isolates could not be classified at the species level, the similarity ratio was low, they formed a distinct group that was supported by strong bootstrap values in the phylogenetic tree, and the differences discovered in the network analysis revealed the diversity among the isolates and gave important findings that these isolates may be new species.