Ecology, Environment and Conservation Paper


Vol. 32 (January Suppl. Issue): 2026

Page Number: S231-S236

MORPHOLOGICAL, BIOCHEMICAL, AND MOLECULAR CHARACTERIZATION OF RHIZOBIUM SP. ISOLATED FROM LEGUME ROOT NODULES

Soundaryashree K.R., Bhavana D., Ashwini J., Shivarudraswamy D., Kumar J.R. and Nagalambika Prasad

Abstract

The present study aimed to isolate and identify Rhizobium species from root nodules of leguminous Trigonella foenum-graecum and Mimosa pudica plants collected from rural regions of Karnataka, India. Root nodules were extracted from healthy plants, and isolates were cultured on Yeast Extract Mannitol Agar (YEMA). Biochemical tests such as catalase, oxidase, indole, MR-VP, and citrate utilization confirmed Rhizobium characteristics. Optimization studies on pH, temperature, and inoculum size were conducted to assess growth efficiency. Biomass evaluation identified the most efficient isolate, which was subjected to molecular identification through DNA extraction using the CTAB method, PCR amplification, and sequencing. The study confirmed the presence of efficient Rhizobium strains with potential applications in nitrogen fixation and sustainable agriculture.