Effect of carp and fish feed on yield and soil nutrient availability under integrated rice-fish culture

摘要

The field experiment was carried out during the rainy season of 1997 and 1998 in the coastal alluvial soil (initial available N: 171 kg centre dot ha~(-1), available P_2O_5: 22.4 kg centre dot ha~(-1) and available K_2O: 156.7 kg centre dot ha~(-1),pH 7.0) of South 24-parganas district of West Bengal, India. Both grain and straw yield of tall indica rice (variety: NC 492) were significantly higher under all types of carp (Labeo rohita Ham., Catla catla Ham., Cirrhinus mrigala Ham.) over no fish. Application of fish feed not only increased the fish yield by 7 percent but also increased the grain and straw yield of rice by 19 and 13 percent respectively. Introduction of carps in rice field and application of fish feed improved the nitrogen, phosphorus and potassium availability in soil.