Studies on Molecular Identification of Anabaena Cyanobionts of Azolla Species

Azolla is a genus of free-floating water fern which is widely distributed in aquatic habitats of the tropics and temperate regions. It is one of few vascular plants known to exhibit a symbiotic association with N2fixing blue green algae, Anabaena sp. In view of this, a study was carried out on molecular identification of Anabaena strains isolated from three Azolla species. The selected Azolla species were grown in culture medium prepared with garden soil, goat manure, super phosphate and its combinations. The three strains of Anabaena cyanobiants present in the leaf cavity of three different Azolla species were isolated and grown in BG11 medium. Out of three Anabaena isolates, only two isolates (i.e., strains -1 & 2 isolated from Azolla microphylla and A.filiculoides respectively), were able to grow an BG11 medium while other strain isolated from A.pinnata have not grown on the culture medium. These two Anabaena cyanobiants were further mass cultured in BG11 medium and were identified through molecular studies using 23S r RNA sequencing. Thus, the two selected strains were identified as Anabaena sphaerica (KX055938) and A.variabilis (KX055939).