Diallel Analysis of Wheat Parents and Their F2 Progenies under Medium and Low Level of Available N in Soil

ABSTRACT Due to high production cost and prevention of environmental pollution, it is important to reduce the amount of nitrogen (N) fertilizer used on wheat (Triticum aestivum L.). The aim of this study was to evaluate N use of 6 × 6 diallel wheat F2 progenies and parental lines at low (N0, no N fertilizer) and high (N+, 160 kg N ha− 1) N levels. Significant differences were found between N+ and N0 application in grain N content, grain N yield, N use efficiency for grain N yield (NUEgn), and N use efficiency for grain yield (NUEgy). The cultivar ‘84CZT04’ showed positive and high general combining ability (GCA) effects for all traits at low N level. Also, it was the best combiner for all traits at both N levels. The cultivar ‘Genc 99’ was the best parent for GCA effects for grain yield and NUEgy. Hybrids ‘Genc 99 × 84CZT04’ and ‘84CZT04 × Weaver’ showed positive specific combining ability (SCA) effects for all investigated traits at low and high N levels. Variety ‘84CZT04 × Apogee’ had the best SCA effec...