Characterization of PGPR from rhizospheric soil of some vegetable crops cultivated at Sylhet district of Bangladesh

Plant Growth Promoting Rhizobacteria (PGPR) are rhizosphere-dwelling microorganisms which hold a great deal of potential for both plant growth stimulation and disease prevention. The characterization of PGPR will aid in the advancement and deployment of biocontrol agents. In this present work, rhizospheric soils were collected from several locations of Sylhet Agricultural University in order to obtain plant growth promoting rhizobacteria. Nineteen bacterial samples were extracted from a variety of fifteen distinct vegetable crops, viz. tomato, brinjal, beans, okra, cabbage, cauliflower, pumpkin, amaranth, malabar spinach, bitter gourd, ridge gourd, spiny gourd, sponge gourd, wax gourd, and snake gourd. These isolates were examined morphologically, biochemically, and screened for plant growth stimulating capability as well as their efficacy in combating the plant pathogen Fusarium oxysporum through antifungal activity. Among the isolates, only Lysinibacillus macroides (RB2), Lysinibacillus fusiformis (RB6) and Acinetobacter baumannii (RB15 and RB17) showed antifungal and growth promotion potentials. Therefore, the present study indicates that the vegetable rhizosphere contains potential rhizobacteria which could be utilized to enhance plant development and reduce disease incidence on vegetable crops.