title: Deviation from the grain protein concentration-grain yield negative relationship is highly correlated to post-anthesis N uptake in winter wheat.
abstract: In plants, carbon and nitrogen (N) economies are intimately linked at the physiological and biochemical level. The strong genetic negative correlation between grain yield and grain protein concentration observed in various cereals is an illustration of this inter-relationship. Studies have shown that deviation from this negative relationship (grain protein deviation or GPD) has a genetic basis, but its physiological basis is still poorly understood. This study analysed data on 27 genotypes grown in multienvironment field trials, representing a wide range of agricultural practices and climatic conditions. The objective was to identify physiological processes related to the genetic variability in GPD. Under most environments, GPD was significantly related to post-anthesis N uptake independently of anthesis date and total N at anthesis. The underlying physiological trait might be related to genotypic differences in either access to soil N, regulation of N uptake by plant N status, or ability to maintain root activity during the grain-filling period. GPD is an interesting potential target in breeding as it appears to be relatively robust across different environments and would be valuable in increasing total N uptake by maturity.
authors.affiliation: INRA, UMR 1095 Génétique, Diversité et Ecophysiologie des Céréales, 234 Avenue du Brézet, F-63100 Clermont-Ferrand, France.
authors.forename: Matthieu
authors.initials: M
authors.lastname: Bogard
authors.forename: Vincent
authors.initials: V
authors.lastname: Allard
authors.forename: Maryse
authors.initials: M
authors.lastname: Brancourt-Hulmel
authors.forename: Emmanuel
authors.initials: E
authors.lastname: Heumez
authors.forename: Jean-Marie
authors.initials: JM
authors.lastname: Machet
authors.forename: Marie-Hélène
authors.initials: MH
authors.lastname: Jeuffroy
authors.forename: Philippe
authors.initials: P
authors.lastname: Gate
authors.forename: Pierre
authors.initials: P
authors.lastname: Martre
authors.forename: Jacques
authors.initials: J
authors.lastname: Le Gouis
mesh_terms: D004777:Environment; D035264:Flowers / Q000502:physiology*; D005838:Genotype; D016014:Linear Models; D009584:Nitrogen / Q000378:metabolism*; D010641:Phenotype; D010940:Plant Proteins / Q000378:metabolism*; D012621:Seasons; D012639:Seeds / Q000254:growth & development* / Q000378:metabolism*; D014908:Triticum / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*
chemical_list: D010940:Plant Proteins; D009584:Nitrogen