Characterisation of phosphate solubilising bacteria Pseudomonas sp and evaluating its efficacy as biofertilizer and biocontrol agent for soybean cropping system

Abstract

The present research was conducted with the bacterial culture that was procured from the Barkatullah University, Bhopal (M.P.). Based on morphological, colonial, and Molecular characterization the bacterial isolate was identified as Pseudomonas fluorescens. This isolate was then assessed for its PGPR and biocontrol attributes such as IAA , Phosphate Solubilization , HCN Siderophore yield .The enzymatic activity of pseudomonas had shown amylase, cellulase, and chitinase and lipase activity. In the further experimental analysis, it has been observed that this organism has potential antagonistic activity against three different fungal pathogens of soybean viz. Rhizoctonia solani, Colletotrichum truncatum, and Fusarium oxysporum .After analysing its fungal inhibition efficiency the metabolite responsible for efficient fungal inhibition was characterized.Based on the different properties the metabolite was identified as 2,4 DAPG. Optimization of 2,4 DAPG production, phosphate solubilizing efficiency was performed by OFAT, Plackett Burman design, Response Surface methodology. Successful scale-up fermentation process conducted in 2.5L bioreactor and the solubilization of phosphate was maximized up to 45% then initial value, while the production of 2,4 DAPG was maximized up to 34% then initial value. The biocontrol and biofertilizer effect of Pseudomonas fluorescens was seen on soybean crops. Maximum results were found in the treatment T3, which contains 0.05% of carbendazim with Pseudomonas. Along with the significant change in the soil, properties in all treatments as compared to control confirmed the success of implementation of this sustainable approach (T3) in the soil. newline