RELATION OF NITROGEN-UTILIZATION TO YIELD COMPONENTS IN SOFT RED WINTER-WHEAT

This study was conducted to characterize soft red winter wheat (Triticum aestivum L.) cultivars for nitrogen (N) utilization efficiency and to determine which traits were most affected and the predictive value of these traits. Grain yield, number of spikes per m(2), kernels/m(2), kernels/spike and 1,000 kernel weight (TKW) were measured at maturity. Data were collected for three growing seasons from field plots grown on a silt loam and one growing season on a sandy loam, Results indicated that N utilization efficiency was not associated with grain yield. Kernels/m(2) had the highest correlation with grain yield (r = 0.50) of the yield components. Kernels per spike had a correlation of 0.43 with grain yield. However, TKW was not correlated with grain yield. There was variation among cultivars as to how the yield components produced final grain yields. Path coefficients indicated a strong positive direct effect for kernels/spike on grain yield and N utilization efficiency. Kernels/spike was found to be the most effective trait to be used as a predictive value for grain yield and N utilization efficiency.