GENETIC DIVERSITY AND PHENOTYPIC VARIATION IN MARGINAL POPULATIONS OFTHE LOCALLY ENDANGERED SPECIES HORDEUM-SECALINUM (POACEAE)

Electrophoresis was used to compare variation in hordein polypeptide p atterns and isozymes in five marginal populations of Hordeum secalinum (four Swedish and one Danish population) and four populations along t he Atlantic coast from Denmark to Spain. Hordein patterns were uniform within and among Swedish and Danish populations whereas the materials from France and Spain were divergent. The banding patterns for nine i sozymes (AAT, IDH, MDH, PGD, GPI, ME, ACP, EST, and PRX) agreed with t hose reported for other Hordeum species. All putative loci were monomo rphic with the exception of PRX, which showed three different phenotyp es. The five marginal populations varied in seed set and cultivated pl ants differed in phenological traits.