RELATIONS BETWEEN SEED STORAGE PROTEINS AND MALTING QUALITY IN 2-ROWED BARLEY (HORDEUM-VULGARE L)

Seed endosperm storage proteins were separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) in 57 two-rowed barley cultivars and lines (Fig. 1), most of which were bred in Japan. Hordein major seed storage proteins were divided into 4 groups, A, B, C and D, according to their molecular masses. The B (B1, Bi*, B2 and B2*) and C (C1, C2, and C3) hordeins were major proteins in these cultivars and lines, generating different types of electrophoretic patterns (Fig. 2), which were found to be closely related to the malting quality such as the extract yield, soluble nitrogen content, Kohlbach index and diastatic power which was examined previouly (Table 1). The cultivars and lines with the B1C3 and B1*C3 types of hordein were considered to have significantly high malting quality. Furthermore, seed endosperm proteins from another 8 Japanese cultivars and 82 cultivars from the other countries were separated by SDS-PAGE (Fig. 5). The electrophoretic patterns of hordein obtained, were different from the hordein types described above. This indicates that there should be wide genetic variation of hordein in two-rowed barley.