"Studies on the Biodiversity of diazotrophs from the rhizospheric and nonrhizospheric regions of rice plants and their use in biofertiliser technology development with special reference to Karimganj District of Barak Valley region of South Assam" is the record of work done by me. Assam is one of the seven states of North East India. The present study revealed that the acidic rice field soil of south Assam harboured a good number of Sphingomonas azotifigens, Pseudomonas putida, Herbispirillum sp, Acinetobacter radioresistance, Herbispirillum rubrisubalbicans, Stenotrophomonas maltophila,...