EXPLORING THE ABIOTIC AND BIOTIC STRESS TOLERANCE POTENTIAL OF RHIZOBACTERA ISOLATED FROM CYAMOPSIS

Abstract

Agriculture plays a vital role for any economy primarily for developing and under developed economies. Increasing abiotic as well as biotic stresses adversely affects crop productivity across the world. Microorganisms inhabiting the Rhizospheric region of plant soil are known to play an important role in alleviating these stresses, thus enhancing crop productivity and yield. The present study was carried out to isolate the Rhizospheric bacteria from Cyamopsis showing potential to tolerate abiotic and biotic stresses. To carry out this, bacteria were isolated from Rhizospheric soil of Cyamopsis which were collected from different regions of Gujarat. These isolates were screened for tolerance to different abiotic stresses such as temperature, pH, salt and drought. Highly abiotic stress tolerant isolates were further tested for biotic stress against pathogenic bacteria and fungi. Among the 80 bacterial isolates, best grown 30 cultures were tested for different abiotic stress. Four cultures i.e. MN40, KM1, KM6 and AK17 showing high tolerance to abiotic stresses were further investigated for biotic stress tolerance. Selected cultures were tested for their antagonistic activity against pathogenic fungi viz., Macrophomina phaseolina, Fusarium oxysporium, Sclerotinum rolfissii and Trichoderma spp. Furthermore, antimicrobial activities of all 4 selected bacterial strains were tested against different test organisms viz., Gram negative bacteria (Salmonella typhi) and Gram positive bacteria (Staphylococcus aureus, Bacillus subtilis, Micrococcus luteus). Amongst the 4 selected bacterial strains, KM6 shows highest antagonistic activity.