Genetic variation and heritability of grain protein deviation in European wheat genotypes.

•Grain protein deviation has been determined for European wheat cultivars grown in multi-environment trials.•Significant variation has been demonstrated, in mean GPD and in stability between environments.•The variation in GPD has been apportioned between the effects of genotype, environment and G x E interactions.•GPD is an attractive target for breeders to improve NUE and reduce the nitrogen requirement for breadmaking wheat.