Response of rice to an Integrated Nutrient Management treatment in soils collected from the long term fertility experiment

A long-term fertility experiment was initiated during Kharif 1996 at Regional Agricultural Research Station (RARS), Titabor. Soil samples from four treatments viz control, 100 per cent N, 100 per cent NPK and 50 per cent N (Urea) + 50 per cent N (FYM) + 100 per cent PK after 12 years of this experiment were collected at the time of harvest of Winter rice 2007. Pot experiments were conducted for Summer rice 2008 to determine resilience of soils of four treatment plots of the long term fertility experiment. Application of an Integrated Nutrient Management (INM) package to the soils of different treatments in pot increased grain yield and other dry matter yield. In soils of treatments 3 and 4 response to the INM package in terms of grain yield of Summer rice was more than other treatments (9.6 to 16.8% increase in grain yield over the normal field treatments). The results suggested that cultivation of rice for 12 years brought significant change in soil quality parameter and resilience of soil was adversely affected. These results also suggested that deterioration of soil under rice-rice cropping system could be reduced by application of balanced fertilizers and combined application of organic and inorganic fertilizers.