Construction of barley consensus map showing chromosomal regions associated with economically important traits
In the past, it has been difficult to accurately determine the location of many types of barley molecular markers due to the lack of commonality between international barley linkage maps. In this study, a consensus map of barley was constructed from five different maps (OWB, VxHs, KxM, barley consensus 2 and barley consensus 2003) to produce the consensus AD-2005 map with 1536 markers. The QTL that have been identified in previous barley studies were then incorporated into the integrated consensus map to provide a quick method of aligning and comparing barley linkage maps and to identify markers closely linked to barley traits. The markers placed on this map are consistent with respect to order on the chromosomes with the individual maps and other barley maps with a few minor differences. The consensus AD-2005 was compared with rice Cornell RFLP map to examine the reliability of the constructed map in comparative genomic studies. Unlike previous consensus maps, the purpose of this consensus map (containing QTL) is to provide a tool for scientists to accurately locate molecular markers to chromosome regions responsible for economically important traits. It is estimated that markers placed on the consensus map are located very close to their true positions as determined by the five maps used in this study. It is envisaged that the consensus map will benefit small-grain researchers by providing an efficient means of choosing markers of interest and identifying QTL regions for future genetic or plant breeding studies on a worldwide basis.
Keywords: Barley, QTL, genetic linkage mapping, consensus map, comparative genome mapping