Development of cyanobacterium-based biofilms and their in vitro evaluation for agriculturally useful traits

The ability of cyanobacteria to be useful as matrices for agriculturally important bacteria was evaluated. Biofilms were generated with the selected strain Anabaena torulosa after co-culturing with Azotobacter chroococcum, Pseudomonas striata, Serratia marcescens, and Mesorhizobium ciceri. The biochemical attributes were compared with individual bacterial and cyanobacterial cultures. The biofilms were characterized in terms of proteins, chlorophyll, IAA production, acetylene-reducing activity, phosphate solubilization, and antagonism towards selected phytopathogenic fungi. An enhancement in the population counts was recorded in A. torulosa-S. marcescens and A. torulosa-P. striata biofilms. The A. torulosa-A. chroococcum and A. torulosa-M. ciceri biofilms were also able to utilize new saccharides as compared to the individual cultures. Such novel biofilms with agriculturally useful traits can provide additional advantages including the broader spectrum of activity and the presence or formation of biologically active compounds; they also suggest the way to effective inoculants for sustainable and environment friendly agriculture.