Genotypic Variation for Yield and Grain Protein Concentration and its Relationship with Nitrogen Remobilization in Iranian Wheat

The aim of this study was to investigate the genotype effect on nitrogen remobilization and its relationship with yield and grain protein concentration in genotypes of wheat during grain filling. Twelve wheat cultivars different in origin and varying with grain yield and grain protein percentage were selected. A randomized complete block design was used. Plants were harvested at anthesis and maturity and divided into leaf, culm, chaff and grain. Compared with different organs, the leaf had the highest nitrogen content at anthesis indicating that leaf is a major nitrogen source for grain development. Cultivars had significant differences in term of N remobilization. Among cultivars, the highest N remobilization was recorded for Karkheh and Zarin. Our experiment showed that the nitrogen remobilization efficiency varied from 86.31 for Karkheh to 59.47 for Karaj1.The highest grain yield across the cultivars was observed for Pishtaz and the lowest for Azar2, whereas Azae2 had the highest protein percentage. The negative correlation between grain N concentration and grain yield was found, suggesting that genotypes exhibiting both high yield and high grain N concentration might be selected. Supporting the agreement above are, for instance, cultivars Falat and Chamran that were high in grain yield, grain N concentration and N remobilization efficiency.