Effects of different fertilization and feeding regimes on the production of integrated farming of rice and prawn Macrobrachium rosenbergii (De Man)

An experiment was conducted in rice fi eld plots each of 30 m 2 to determine the appropriate combination of feeding and fertilization regimes for the giant freshwater prawn Macrobrachium rosenbergii (De Man. 1979) cultured along with rice in rice fiThere were four treatments: rice culture only with regular fertilization (A, control); rice-prawn integrated culture with regular fertilization (B); rice-prawn integrated culture with basal fertilization and commercial feed (C); and rice-prawn integrated culture with regular fertilization and commercial feed (D). Juvenile prawns of 1.5-g size were stocked on the third day after rice transplantation at a density of 2 prawns m -2 and fed twice daily at 5% reducing to 2% of body weight during the experiment. The rice yield in treatment D (0.42 kg m -2 ) was signifi cantly higher than that in other treatments (0.34, 0.36, 0.34 kg m -2 in treatments A, B, C respectively). Prawns grew signifi cantly faster ( P 0.05). Treatment C gave the highest economic returns among all treatments, followed by treatments D and B, indicating that eh combination of basal fertilization and commercial feed is the most appropriate nutrient input regime for the rice-prawn integrated culture system.