Nitrogen Use Efficiency: Relevant Traits and Inheritance, Keys to Enhancing Wheat Productivity Under Low N-Input

To meet the demand of a rapidly increasing population, increasing wheat yield and improving nitrogen use efficiency NUE by optimizing N management can significantly enhance agricultural sustainability in developing countries like Egypt, especially in light of climate change concerns. Hereby, six parents i.e. 1) Line 1, 2) Line 2, 3) Line 3, 4) Sakha 93, 5) Giza 168 and 6) Gemmeiza 10 were crossed in a half diallel fashion to obtain information about performance, important criteria, nature of gene action and heritability for N-efficiency measurements. The amount of available soil nitrogen was estimated and found to be 40.5 kg N/fad. which expressed as low nitrogen level (L1), then 35 Kg N/fad was added to give 75.5 kg N/fad which represents the normal level (L2) and 70 kg N/fad was added to give 110.5 Kg N/fad as high N–level (L3). Thus, three adjacent experiments were conducted for the three nitrogen levels, separately in a RCBD with three replicates. Results of NUE components indicate that the parental wheat genotypes P1, P2 and P6 and their F1 crosses P2 x P5 and P3 x P4, P4 x P6 made more efficient use of each observed amount of nitrogen uptake for grain and straw yield.