Breeding for nitrogen use efficiency in organic wheat systems

Summary

Improving crop nitrogen use efficiency (NUE) is important to reducing the environmental impacts of agriculture, for both perennial and annual crops. This study tested winter wheat breeding lines developed in organic and conventional systems, historic wheat varieties and perennial wheat under organic management. There were significant differences among selection categories and among genotypes. However, standard methods of measuring NUE may not be appropriate when the breeding objectives are to reduce N use. Alternative methods of evaluating breeding materials, including regression analysis of grain protein deviation (GPD) and principal component analysis (PCA) were explored. GPD was not found to discriminate well between genotypes in this study, but PCA showed promise in examining the relationship among measured variables and among genotypes.