IDENTIFICATION AND GENETIC-DISTANCE ANALYSIS OF WHEAT CULTIVARS USINGRAPD FINGERPRINTING

Five South African wheat cultivars and five foreign Russian wheat aphi d (Diuraphis noxia Mordvilko) resistance source cultivars were fingerp rinted using RAPD analysis. These cultivars are being used in breeding programs aimed at developing new D. noxia resistant wheat cultivars. Cultivar, genome and species specific markers were produced through RA PD analysis of wheat (Triticum aestivum L.), triticale (x Triticosecal e Wittmack) and rye (Secale cereale L.) genomic DNA using twenty nine oligonucleotide primers. These markers were used to construct a RAPD f ingerprinting profile that distinguished all the cultivars included in the study. A total of 239 scorable RAPD loci were used to calculate p airwise genetic distances which revealed an average distance of 6.9% b etween the local susceptible and foreign resistance source cultivars. Unweighted pair-group mean arithmetic (UPGMA) cluster analysis of the genetic distance data yielded a dendrogram that was consistent with th e known genetic relationships and pedigrees of the cultivars in the st udy.