Standardization of Media for Co-Culturing of Azospirillum, Phosphobacteria and Methylobacterium (Azophosmet)

Nitrogen fixers, phosphate solubilizers and a plant growth hormone synthesizer were cocultured in a suitable single medium The compatibility nature of Azospirillum brasilense Sp7, Bacillus megaterium var phosphaticum PB1 and Methylobacterium extorquens CO 47 in a common growth medium was investigated to coculture the bioinoculants (Azophosmet). All the three had better growth in YEMA. During coculturing the survival of Azospirillum Sp7, PSB PB1 and PPFM CO 47 was maximum in YEMB supplemented with 0.5% methanol. Biochemical characters of YEMB culture filtrates (0.5% methanol) recorded the highest amount of ammonia secretion, cell protein and polysaccharide content when compared to nutrient broth and glycerol peptone broth. The shelf life studies of Azophosmet in lignite carrier based formulation assessed for four months indicated that Azospirillum Sp7, PSB PB1 and PPFM CO 47 had cell load of 10⁸cfu g^-1. The cotton seeds treated with the Azophosmet revealed the surviving ability of Azospirillum Sp7, PSB PB1 and PPFM CO 47 noticed up to 24 hr on the seeds.