The use of AFLPs to examine genetic relatedness in barley

The generation of AFLPs in spring barley cultivars provided genetic information relating to the development of the crop in the UK since 1953. Principal co-ordinate (PCO) analysis of genetic similarities (gs) confirmed the marked contrast in the cultivars used in the 1970s and 1980s. The earliest cultivars, many derived from Proctor, were succeeded by tall-strawed, disease-resistant types with high yield but poor malting potential. In the 1980s they were in turn replaced by short-strawed cultivars with excellent yield and good malting quality, which originated from Triumph. A PCO plot of gs provided insight into the effects of selection for disease resistance and the antagonism between malting quality and particular resistance genes. The analysis of gs was more useful than pedigrees and estimates of kinship in revealing the genetic relationship between cultivars. Theoretical considerations for maximising the efficiency of an AFLP genotyping programme are discussed in the context of the number of primer pairs required to distinguish genotypes at varying levels of similarity.