The extent and structure of genetic variation in species of the sitopsis group of aegilops

The extent and structure of genetic variation in 21 populations covering the five species of the Sitopsis group of Aegilops were investigated by analysis of electrophoretically discernible water soluble leaf proteins. Sixteen loci were examined. All loci were polymorphic across the five species. Over 40 per cent of the alleles were found in all five species and only three rare alleles were species- specific. Genetic diversity was high (D = 0.267) with 51 per cent of the total diversity contributed by within-population diversity, 16 per cent by diversity between populations within a species and 33 per cent by diversity between species. Over all 21 populations the mean number of alleles per locus per population was 1.57 and the proportion of polymorphic loci was 0.38. Aegilops speltoides was genetically distant from the other four species, Ae. bicomis, Ae. longissima, Ae. searsii and Ae. sharonensis. Aegilops sharonensis was found to be equally close to Ae. longissima and Ae. bicomis. Aegilops searsii was equally distant from Ae. longissima, Ae. bicomis and Ae. sharonensis.