Productivity, Nutrient Balance, Soil Quality, and Sustainability of Rice (Oryza sativa L.) under Organic and Conventional Production Systems

A field experiment was conducted for 5 years (2004–2005 to 2009–2010) covering 10 crop seasons [five wet (WS; Kharif) and five dry (DS; Rabi)] at the Directorate of Rice Research farm, Hyderabad, India, to compare the influence of organic and conventional farming systems on productivity of fine grain rice varieties, cumulative partial nutrient balance, and soil health/quality in terms of nutrient availability, physical and biological properties, and sustainability index. Two main plot treatments were with and without plant protection measures, and four subplot treatments were (1) control (CON), (2) inorganic fertilizers (CF), (3) organics (OF), and (4) inorganics + organics (integrated nutrient management, INM). During wet season, grain yields with CF and INM were near stable (5.0 to 5.5 t ha−1) and superior to organics by 15–20% during the first 2 years, which improved with OF (4.8 to 5.4 t ha−1) in the later years to comparable levels with CF and INM. However, during DS, CF and INM were superior to OF f...