Molecular marker for protein Z content in barley (Hordeum vulgare L.)

Protein Z, a major water- soluble seed protein of barley, is thought to be one of the factors influencing foam stability of beer. To find the breeding material for raising the protein Z content in malting barley, we surveyed the protein Z contents of malting barley varieties. Generally, North American six-row varieties had higher contents than Japanese varieties. Especially, variety Bonanza had the highest protein Z content among the 62 varieties surveyed. Using the lines derived from the crosses between Bonanza and the Japanese malting varieties, we found that the protein Z structural gene region contributed to the protein Z content of seeds. We also estimated the position of protein Z structural gene on chromosome 4H using a set of RFLP markers. Consequently, we concluded that the high protein Z content of Bonanza could be introduced and screened by the RFLP patterns of the protein Z structural gene.