Yield and Nitrogen Utilization by Wheat in Relation to Moisture and Fertility Levels

Abstract

Studies undertaken to determine the effect of three moisture levels created by irrigating when available water in 0-30 cm soil depth was 30, 50 and 70% (designated respectively as I₀, I₁and I₂)indicated that as the moisture supply was increased from I₀ to I₂ level, the yield increased to an extent of 33%. On each of these moisture levels, the N-Yield relationship was curvilinear, the association, however, was close (R² = 0.82) at I₁ level of irrigation. With increase in moisture supply the general trend was one of a modest decrees in per cent N in grains and N requirements, but the N uptake showed steady increase. use efficiency of applied N increased with increase in moisture supply but decreased with increasing levels of nitrogen. from this study it seems that irrigation 50% water depletion level (which corresponded to an average 11 - days irrigation interval) and 80 kg N/ha make a suitable water nitrogen combination for optimum yield of wheat and nitrogen utilization under limited water and fertilizer supplies.