COMPARATIVE-ASSESSMENT OF GENETIC DIVERSITY IN WILD AND CULTIVATED BARLEY USING RIBOSOMAL DNA SPACER LENGTH VARIANTS

Ribosomal DNA spacer length variants (slv) were used to compare the ge netic diversity between Hordeum spontaneum, the supposed progenitor of cultivated barley, and landraces of barley, H. vulgare, collected fro m three countries in the eastern Mediterranean region. A total of six rDNA slv and six slv phenotypes were observed. All six slv and phenoty pes were found in both species. Nei's heterozygosity index was higher for landraces in all three countries. Landraces possessed slightly hig her diversity than H. spontaneum. Slv phenotype 1 (112, 104) was the m ost predominant type in both species, and the frequency distributions for the two species were similar. This suggests that H. vulgare and H. spontaneum belong to the same polymorphic species. Furthermore, H. sp ontaneum seen today in the eastern Mediterranean region might have bee n derived from an extinct two-rowed ancestor.