1. High diversity of genes for nonhost resistance of barley to heterologous rust fungi
- Author
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Rients E. Niks, Thierry C. Marcel, Hossein Jafary, and Giorgia Albertazzi
- Subjects
Population ,Quantitative Trait Loci ,Heterologous ,Quantitative trait locus ,Biology ,Plant disease resistance ,Investigations ,Genes, Plant ,leaf rust ,Laboratorium voor Plantenveredeling ,puccinia-hordei ,Chromosome Segregation ,Sequence Homology, Nucleic Acid ,Genetic variation ,Genetics ,education ,Crosses, Genetic ,Plant Diseases ,Puccinia ,education.field_of_study ,Chi-Square Distribution ,EPS-2 ,plants ,fungi ,Fungi ,food and beverages ,Chromosome Mapping ,Genetic Variation ,pathogens ,Hordeum ,biology.organism_classification ,linkage map ,Immunity, Innate ,defense ,Plant Breeding ,Phenotype ,qtls ,identification ,Hordeum vulgare ,Lod Score ,Puccinia hordei ,accumulation ,iii effector - Abstract
Inheritance studies on the nonhost resistance of plants would normally require interspecific crosses that suffer from sterility and abnormal segregation. Therefore, we developed the barley–Puccinia rust model system to study, using forward genetics, the specificity, number, and diversity of genes involved in nonhost resistance. We developed two mapping populations by crossing the line SusPtrit, with exceptional susceptibility to heterologous rust species, with the immune barley cultivars Vada and Cebada Capa. These two mapping populations along with the Oregon Wolfe Barley population, which showed unexpected segregation for resistance to heterologous rusts, were phenotyped with four heterologous rust fungal species. Positions of QTL conferring nonhost resistance in the three mapping populations were compared using an integrated consensus map. The results confirmed that nonhost resistance in barley to heterologous rust species is controlled by QTL with different and overlapping specificities and by an occasional contribution of an R-gene for hypersensitivity. In each population, different sets of loci were implicated in resistance. Few genes were common between the populations, suggesting a high diversity of genes conferring nonhost resistance to heterologous pathogens. These loci were significantly associated with QTL for partial resistance to the pathogen Puccinia hordei and with defense-related genes.
- Published
- 2008