Analyses of diversity among fungicidal Anabaena strains

This study characterized 28 Anabaena strains exhibiting fungicidal activity using different molecular approaches. Based on 16S rDNA and internal transcribed spacer region sequences, all the Anabaena strains isolated from India were found genetically diverse from the other reference strains in the National Center for Biotechnology Information database. Out of these, six belonging to five different species were found to produce microcystin toxins as confirmed by polymerase chain reaction amplification of microcystin synthase gene and an enzyme-linked immunosorbent assay-based method. All the sequenced Anabaena strains with the fungicidal trait formed a separate group in both the trees, when compared to other reference Anabaena strains. Thus, it can be hypothesized that the antifungal trait has led to evolutionary divergence among these strains. This study illustrates the diversity among the Anabaena strains with fungicidal activity and their uniqueness vis a vis Anabaena strains available globally.