Characterization of Rhizobium strain isolated from the roots of Trigonella foenumgraecum (fenugreek)

Abstract

Trigonella foenumgraecum (fenugreek) is known for its dietary protein source, medicinal properties and symbiotic nitrogen fixation by Rhizobium present in its root nodules. The present study describes the characterization of a Rhizobium strain isolated from root nodules of fenugreek. The Rhizobium isolates were rod shaped, gram negative, acid and mucous producing. They were found to be temperature and pH sensitive, with optimum values of 29.4 and 7.0°C, respectively. The bacteria was sensitive to the antibiotics; chloramphenicol, kanamycin and streptomycin. It utilizes glucose, sucrose and starch as sole carbon source. The Rhizobium species isolated from fenugreek roots have the potential to produce industrially important enzymes; amylase and cellulase. Immobilizing the organism in agar and agarose does not affect its activity; indeed increased biomass yield and enzyme production was observed. The Rhizobium can be easily immobilized onto carriers like charcoal powder which can be applied as biofertilizer.