یوسف ارشد - Department of Genetics and National Plant Gene Bank of Iran, Seed and Plant Improvement Institute, Agricultural Research, Education and Extension Organization (AREEO), P. O. Box: ۳۱۳۵۹-۳۳۱۵۱, Karaj, Iran.
مهدی زهراوی - Department of Genetics and National Plant Gene Bank of Iran, Seed and Plant Improvement Institute, Agricultural Research, Education and Extension Organization (AREEO), P. O. Box: ۳۱۳۵۹-۳۳۱۵۱, Karaj, Iran.

In order to evaluate the traits related to nitrogen utilization and to identify the superior genotypes, ۳۳ bread wheat landraces along three check cultivars of Chamran and Koohdasht (from Iran) and Gobustan (from the Republic of Azerbaijan) were studied in simple lattice statistical design with two replications under two treatments of non-usage and application of ۲۰۰ kg/ha ammonium nitrate fertilizer in research field of Seed and Plant Improvement Institute located in Karaj, Iran. The results indicated that the diversity of nitrogen uptake was higher than that of nitrogen use efficiency based on coefficient of variation. Genotype ۴ (from Iran) and Chamran showed the highest value of nitrogen uptake efficiency. The highest amount of nitrogen use efficiency belonged to the genotypes ۴ and ۷ (from Iran). In the biplot of nitrogen uptake and use efficiency, check cultivar Chamran along with genotypes ۴, ۱۹, ۲۱ and ۲۳ (from Iran) and ۲, ۳ and ۹ (from the Republic of Azerbaijan), which were superior for both traits were located in region A of Fernandez grouping. Generally, based on the results , a high varation in nitrogen components was revealed in the studied germplasem, particullary in Iranian landraces which could be used as gene pool for breeding programs.

Gene pool, Landrace, Nitrogen yield of grain, Nitrogen biological efficiency