Long-Term Yield of Rice-Rice System with Different Nutrient Management in Eastern India: Effect of Air Temperature Variability in Dry Season

摘要

Maximum and minimum temperatures play an important role in determining yield of rice crop. Yield anomaly of rice under different nutrient management practices was analyzed in a long-term rice-rice system with respect to maximum and minimum temperatures. The treatments included applications of inorganic sources of nutrients (NPK), organic sources of nutrients, i.e., farmyard manure (FYM), combinations of inorganic and organic sources of nutrient (NPK + FYM) and a no nutrient (control). An increase in mean + 1 degrees C for both the maximum and minimum temperatures during the vegetative stage had positive effect on yield, but when the increase was during the reproductive and ripening stages, the effect on the yield was negative effect on yield. The increase in minimum temperature during the vegetative stage, however, had greater positive effect on yield as compared to increase in maximum temperature. Magnitudes of negative yield anomaly due to increase in temperature during reproductive and ripening stages were less in the NPK + FYM treatment (- 0.77 and - 0.74, respectively) than in the control treatment (- 4.52 and - 5.31, respectively). Negative effect of increased temperature during the reproductive and ripening stages on yield anomaly of dry season rice can be minimized by early planting and application of recommended dose of NPK and FYM.