Nitrogen uptake and remobilization from pre- and post-anthesis stages contribute towards grain yield and grain protein concentration in wheat grown in limited nitrogen conditions

Abstract Background In wheat, nitrogen (N) remobilization from vegetative tissues to developing grains largely depends on genetic and environmental factors. The evaluation of potential crops under limited resource inputs such as N supply would provide an opportunity identify N-efficient lines with improved utilisation efficiency yield potential. We assessed the variation in wheat recombinant inbred (RILs) for uptake, partitioning, towards grain, its association grain protein concentration (GPC) yield. Methods used nested mapping (NAM) population (195 lines) derived by crossing Paragon (P) CIMMYT core germplasm (P × Cim), Baj Baj), Watkins Wat), Wyalkatchem Wya). These were evaluated field two seasons supply. plant sampling was done at anthesis physiological maturity stages. Various traits recorded total uptake other related indices calculated. deviation (GPD) calculated regression GPC. grouped into different clusters hierarchical cluster analysis based N-remobilization (NRE). Results accumulation biomass both pre- post-anthesis stages correlated grain-yield. NRE significantly aboveground (AGNa) but negatively associated AGN (AGNpa) suggesting higher till favours high during filling. Hierarchical these RILs resulted four clusters, efficient (31), moderately (59), inefficient (58), (47). lines, AGNa contributed 77% accumulated grains, while it 63% N-inefficient lines. Several also exhibited positive (GPD), combining Among crosses, P Cim superior N-efficient, Wya responded poorly low input. Conclusions propose that favouring or pre-anthesis may be targeted breeding improve grain-yield N. GPD, a first report genotype-dependent GPD AGNpa varieties resources GPC sustainable development conditions.