Linkage relationship between two loci for the barley yellow mosaic resistance of Mokusekko 3 and esterase isozymes in barley (Hordeum vulgare L.).

Abstract

A Chinese landrace of six-rowed barley, Mokusekko 3, has been successfully utllized for introducing its BaYMV resistant gene, Ym, to Japanese malting two-rowed barley. However, information about the location of the Ym locus on a chromosome is limited. The authors almed to confirm the linkage relationship between the Ym locus and complex loci for esterase isozymes, as most of the strains into which the BaYMV resistance from Mokusekko 3 had been introduced showed the same esterase isozyme banding pattern as that of the resistant parent. The linkage analyses revealed that the Ym locus is tightly linked with the complex loci (Est1-Est2-Est4) for the esterase isozymes which are located at the terminal of the long arm of chromosome 3, and that the recombination values ranged from 1.26 to 5.01%. Based on these results, it is concluded that the BaYMV resistant individuals and strains carrying the Ym gene can be easily obtained by selecting the seedlings which show the same banding pattern of esterase isozyme genotype as that of Mokusekko 3, by means of starch gel electrophoresis.