Biofertilizer effect of free living nitrogen fixing bacterium on the growth and water quality properties of Penaeid prawn culture system

The role of phytoplankton is significant in improving the yield of prawn culture. The growth of phytoplankton will be effected various factors viz. dissolved oxygen, production of natural food to shrimp larvae in control of ammonia. The growth of phytoplankton can be enhanced by application of nitrogeneous fertilizers to improve water quality and growth performance of Penaeus indicus. The present research work is focussed on a free-living nitrogen fixing bacterium Azotobacter chroococcum supplemented by nitrogeneous fertilizers to increase the content of proteins, carbohydrates and wet weight of P. indicus. Ten animals of juveniles of P. indicus were collected and grown in controlled conditions for fifteen days. The liquid suspension of free living nitrogen fixing bacteria A. chroococcum has been inoculated for experimental treatment purpose. The inoculum has been introduced to four treatments and for findings of water quality analysis and phytoplankton growth analysis by Strickland and Parsons method and biochemical analysis by Raymont et al., method . The research findings revealed that A. chroococcum supplemented with fertilizers will affect the growth of phytoplankton which is vital in prawn culture and enhance the growth of hormones and dry weight for improvement of the yield.