High-resolution mapping of the nud locus controlling the naked caryopsis in barley

The hulled or naked caryopsis character of barley is an important agronomic trait because of the direct link to its use. A single recessive gene, nud. located on the long arm of chromosome 7H, controls the naked caryopsis character. Previously, linked amplified fragment length polymorphism (AFLP) bands from bulked segregant analysis were screened. and the nud gene was mapped in a population of 151 F, plants. In the present study, the aim was to construct a high-resolution map of the nud gene towards its positional cloning. Two AFLP bands were converted into sequence-characterized amplified region (SCAR) markers (sKT5 and sKT9), and a previously reported SCAR marker sKT3 was improved for more reliable detection of polymorphism. A total of 2380 segregants derived from five cross-combinations were analysed, and the nud gene was flanked by sKT3 and sKT9, at the 0.6-cM proximal and the 0.06-cM distal side, respectively. The SCAR markers developed in this study should be useful for marker-assisted selection in naked barley breeding employing crosses between naked and hulled accessions.