Synopsis Application of 100 pounds N per acre gave optimum yield of rice, provided plants did not lodge before heading. Pre‐heading lodging reduced level of nitrogen consumption and response and the yield. Lodging seemed to be a physiological phenomenon rather than a varietal character. It originated from structural weakness development in culm tissues and was caused primarily by deeper submergence of plants during vegetative growth aided by high nitrogen concentration in soil.

Synopsis Dry matter synthesis and nitrogen and phosphate uptake by rice plant in field culture were highly correlated with grain yield. During intermediate stages of plant development, however, these functions showed steady progress in some centers and different degrees of interruption in some others. The interruptions caused losses in grain yield and were attributable to physiological consequences of lodging.

No abstract

Synopsis Thirty pounds of N per acre caused a significant increase in yield. Responses to bulky organic manure and ammonium sulphate, alone or in combination, were practically identical. Lateritic soils showed a higher grain‐producing capability than low‐land Gangetic alluvium soils of higher fertility status. Yields of grain decreased progressively with delay of planting from mid‐July to mid‐September. Time of application of ammonium sulphate had no influence on rice yield. Split applications were moderately superior to composite applications.