Abstract
Wheat production under climate of northern Iraq depends mainly on annual rain quantity and its distribution. Generally the annual rate is low and poorly distributed ,as a result the yield is low and unstable. Accordingly it has been suggested that small amounts of supplementary irrigation (SI) can alleviate the adverse effects of such unfavorable rain pattern, moreover the optimum dose of nitrogen fertilization is an important factor boosting wheat production and improving quality. The purpose of this study was to investigate the effect of nitrogen fertilizer and abridged (SI) on yield and grain quality. Field experiments were performed during the growing season 2003-2004 at two locations laying out as split-split plot design in RCBD, involving four promising bread cultivars as sub-sub plot, two levels of N fertilizer (zero and 80 kg N/ha) as sub-plot under rainfall alone and with (SI) as a main plot added at booting and heading stages at a rate of 25 mm for each stage. The results showed that N fertilizer had a significant effect on grain yield, grain protein content at both locations. The (SI) affected significantly number of grain/spike, grain yield, the interactions between factors were significant for most characters.
