Abstract

                                Nitrogen fixation by the facultative and anaerobic nitrogen fixing Klebsiella and Clostridium was studied. After characterization cultures were immobilized with sodium alginate and inoculated. A pot culture experiment with IR 50 paddy indicated positive contribution by immobilized cells. The nitrogen fixing ability of the inoculated cultures were estimated using "N technique. The immobilized cells of Clostridium sp. and Klesiella sp. not only fixed the atmospheric N but also enhanced the nitrogen uptake by rice to the tune of 4.22 kg N ha m' and 2.835 kg ha m' respectively.

Key words : Facultative anaerobes, Nitrogen fixation, Immobilization techniques