A core genetic map of Hordeum chilense and comparisons with maps of barley (Hordeum vulgare) and wheat (Triticum aestivum)

Abstract 

The first genetic map of the wild South Ameri- can barley species Hordeum chilense is presented. The map, based on an F₂ population of 114 plants, contains 123 markers, including 82 RAPDs, 13 SSRs, 16 RFLPs, four SCARs, two seed storage proteins and two STS markers. The map spans 694 cM with an average distance of 5.7 cM between markers. Six additional SSRs and seven additional SCARs which were not polymorphic were assigned to chromosomes using wheat/H. chilense addition lines. Polymorphisms were revealed by 50% of the RAPD amplifications, 13% of wheat and barley SSR primers, and 78% of the Gramineae RFLP anchor probes. The utility of SSR and RFLP probes from other Gramineae species shows the usefulness of a comparative approach as a source of markers and for aligning the genetic map of H. chilense with other species. This also indicates that the overall structure of the H. chilense linkage groups is probably similar to that of the B and D genomes of wheat and the H genome of barley. Applications of the map for tritordeum and wheat breeding are discussed.