Characterization and genetic control of the prolamins of Haynaldia villosa: relationship to cultivated species of the Triticeae (rye, wheat, and barley).

Haynaldia villosa is a wild grass of the tribe Triticeae, other members of which include the cultivated cereals barley, rye, and wheat. We have made an electrophoretic and chemical characterization of the major seed storage proteins (prolamins) of H. villosa and determined the chromosomal locations of the structural genes for some components using the available wheat/H. villosa chromosome addition lines. As in wheat, barley, and rye, groups of high molecular weight (polymeric), sulfur-poor (monomeric), and sulfur-rich (monomeric gamma-type and polymeric) prolamins can be recognized. Most of the components are encoded by genes on chromosome 1 Ha, which is homologous with the chromosomes controlling many of the prolamins in wheat and rye and all of those in barley. In addition, H. villosa also contains alpha-type sulfur-rich prolamins, previously detected only in wheat and its close relatives. These may be encoded by genes on chromosome 6Ha, which is homologous with the group 6 chromosomes that control the alpha-type gliadins of wheat. Despite the proposed close relationship between Haynaldia and ryes, no evidence was found for the presence of proteins closely related to the Mr 75,000 gamma-secalins which are characteristic of wild and cultivated species of Secale.