Wheats with purple and blue grains: a review

Summary In addition to white and red grains, wheats with purple and blue grains may occur. Purple grain colour is caused by anthocyanins in the pericarp whereas blue colour is caused by anthocyanins in the aleurone layer. Purple grains occur in tetraploid wheats from Ethiopia, and in one bread wheat accession apparently native to China.Although the use of the purple and blue grain characters as markers has been suggested, their expression is often erratic, especially when heterozygous.No hexaploid wheat with blue grains was described prior to the artificial introgression of genes from diploid wheat and Agropyron species. The number of different sources of blue aleurone gene(s) from Agropyron elongatum is unknown. It is possible that with exchange between researchers the same or related accessions have been used at several research stations. Accessions of diploid wheats are known to possess blue aleurone. The breeding history of a number of purple and blue grained accessions is described. Research should indicate the source species of the gene for blue aleurone of the blue-grained Barevna.