Abstract

The nodulation activity in some legume plants was estimated using two nitrogen fixing microorganisms that produced and introduced in different growth conditions. Two isolates of agriculturally important nitrogen fixing microorganisms, Rhizobium meliloti and Azospirillium lipoferum were isolated from Western Maharashtra soil habitat. The standard isolation technique was carried out in laboratory and was characterized by 16S rDNA method. The growth of mentioned microorganisms was studied at different pH, the optimal pH was found to be 6.5 and 7 for R. meliloti and A. lipoferum respectively. The nodulation activity of R. meliloti was confirmed. Carrier plays an important role in maintaining sufficient shelf life, so,survival of mentioned microorganisms in different carriers at 28°C was deduced. However, lignite was found to be the most efficient carrier for R. meliloti and A. lipoferum to introduce as biofertilizer. The mentioned biofertilizer was checked for colony count to meet the standard requirement (that is, 10⁷cells/g). Furthermore, the mentioned microorganisms were multiplied for mass production using lignite as carrier.

Key words:  Rhizobium meliloti, Azospirillium lipoferum, biofertilizer, lignite.