Monitoring the biofertilizing potential and establishment of inoculated cyanobacteria in soil using physiological and molecular markers

This paper aims to develop methods for quantifying their establishment; using physiological activity (chlorophyll as a growth index and nitrogen-fixing potential as a measure of their biofertilizing capacity), along with evaluation based on DNA fingerprints generated using repeat sequences/palindromes. Time course studies were undertaken in liquid and soil microcosm experiments inoculated with a set of four rhizosphere cyanobacterial strains (BF1 Anabaena sp., BF2 Nostoc sp., BF3 Nostoc sp., BF4 Anabaena sp.). Observations revealed the synergistic effect of three-membered combinations (especially the i.e. BF1 + 2 + 3, 1 + 2 + 4, 1 + 3 + 4) in terms of enhancing chlorophyll and acetylene reducing activity. PCR-based amplification profiles (using short tandemly repetitive repeat (STRR) 1A, STRR_mod, and HIP_AT sequences) proved discriminative in monitoring the presence of the inoculated cyanobacteria in soil microcosm. Future work is in progress to assess the utility of the selected markers/primers in pot experiments, followed by field-level experiments with crop.