Chloroplast DNA diversity in wild and cultivated barley: implications for genetic conservation

Abstract
Nine diverse lines of cultivated barley (Hordeum vulgare) and 11 lines of its wild progenitor (H. spontaneum) were assayed for variation in their chloroplast DNA by digestion with ten restriction endonucleases. The cultivated lines exhibited a single cpDNA polymorphism, whereas the wild material exhibited five. The significantly lower level of diversity among the cultivated lines was unexpected because both cultivated and wild lines had been selected for comparable levels of diversity for nuclear encoded isozyme loci. These results suggest that the level of cytoplasmic diversity was markedly restricted during the domestication of cultivated barley.