Submitted to: Phytopathology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 9/13/1995
Publication Date: N/A
Interpretive Summary: Genetic studies of plant resistance to viruses have been conducted for many years. In some cases, these studies have resulted in improved control of diseases as a result of plant breeders utilizing information derived from genetic studies to develop resistant varieties. Unfortunately, we still do not understand the molecular basis for resistance to viruses. This lack of knowledge is an important barrier to the development of better control measures, especially those which utilize molecular approaches. The purpose of the present work was to identify the number and chromosomal location of genes for resistance to BSMV in barley. We determined that a single gene confers BSMV resistance in Morex barley, and we also determined the location of this gene relative to known molecular genetic markers on barley chromosome 1. Genetic analysis and precise mapping of a barley stripe mosaic virus resistance gene will enable breeders to use molecular approaches to select for BSMV resistance in barley breeding programs. This type of information will also facilitate the development of a more detailed map of barley chromosome 1 in the vicinity of the BSMV resistance gene. This, in turn, may facilitate the isolation and characterization of the BSMV resistance gene itself. Subsequent characterization of this gene will provide information about how plants in general resist virus infection as well as how viruses infect plants. This improved understanding of host-virus interactions will provide valuable clues for the future design of molecular approaches to disease control.
Technical Abstract: The inheritance of resistance to barley stripe mosaic virus (BSMV) in barley was investigated in the Steptoe/Morex doubled haploid population developed by the North American Barley Genome Mapping Project. The number of resistant (68) and susceptible (82) progeny approximated a 1:1 ratio, indicating that a single gene was involved in conferring resistance to BSMV strain CV42 in Morex barley. This resistance gene was mapped to the centromeric region of the short (plus) arm of chromosome 1 based on its linkage to molecular markers on the Steptoe/Morex map. RFLP markers ABC455 and Amy2 were determined to be 1.4 cM distal and 10.3 cM proximal to the resistance gene, respectively. The identification of flanking markers in relatively close proximity may facilitate both the selection for BSMV resistance in barley breeding programs and the high resolution mapping of the centromeric region in the vicinity of this locus.