Molecular characterization of two novel alleles of Hordoindoline genes in Hordeum chilense Roem. et Schult

Grain texture is an important trait in wheat quality, and is related to the presence or absence of puroindolines a and b. In barley, these proteins are synthesised by the Hordoindoline (Hin) genes, orthologs of the Puroindoline (Pin) genes present in bread wheat and Aegilops species. In this study, the variation of Hin genes has been characterized in two representative lines of Hordeum chilense Roem. et Schult., a wild barley species that has been used in the development of a new man-made cereal (tritordeum, ×Tritordeum Ascherson et Graebner). Two novel alleles were detected in this material, one for the Hina-H ᶜʰ 1 gene and another for the Hinb-H ᶜʰ 1 gene. These alleles demonstrated high similarity to the Pin genes of bread wheat, which may explain the soft grain texture of tritordeum. This suggests that the variation present in H. chilense could be utilized in wheat breeding through the use of tritordeum as a bridge species, to extend the range of different textures.