Nitrogen partitioning and remobilization in relation to leaf senescence, grain yield and grain nitrogen concentration in wheat cultivars

AbstractOur objective was to investigate the determinants of genetic variation in N accumulation, N partitioning and N remobilization to the grain post-flowering and associations with flag-leaf senescence, grain yield and grain N% in 16 wheat cultivars grown under high N (HN) and low N (LN) conditions in the UK and France. Overall, cultivars ranged in leaf lamina N accumulation at anthesis from 5.32 to 8.03gNm−2 at HN and from 2.69 to 3.62gNm−2 at LN, and for the stem-and leaf-sheath from 5.45 to 7.25gNm−2 at HN and from 2.55 to 3.41gNm−2 at LN (P<0.001). Cultivars ranged in N partitioning index (proportion of above-ground N in the crop component) at anthesis for the leaf lamina from 0.37 to 0.42 at HN and 0.34 to 0.40 at LN; and for the stem-and leaf-sheath from 0.39 to 0.43 at HN and from 0.35 to 0.41 at LN (P