Plant-cyanobacterial symbiotic somaclones as a potential bionitrogen-fertilizer for paddy agriculture: Biotechnological approaches

The role of N-2-fixing cyanobacteria in improving the fertility of rice pad dy fields is well known. Among all symbiotic associations, involving cyanob acteria, the Azolla-Anabaena complex is very efficient in water-logged rice paddy fields, contributing significant levels of nitrogen and organic matt er thereby improving the physico-chemical properties of soils. This review focuses on some of the recent advances made in the areas of developing gene tically improved somaclones of Azolla-Anabaena associative complex, and art ificial plant-cyanobacterial symbiotic associations.