Pinpointing the genes for partial resistance of barley to a pathogenic rust fungus.
Genetic resistance is a highly effective way to protect crops against diseases. One type of resistance, partial resistance, is of particular interest because the pathogen seems not to be able to adapt to it. Genes for partial resistance reside on “Quantitative Trait Loci (QTLs)”, each with a relatively small contribution to the resistance. The barley – leaf rust relationship served as a model to study the genetic architecture of partial resistance. We found a surprisingly large diversity in QTLs for partial resistance. The incorporation of QTLs into susceptible lines (Near-isogenic lines, NILs) allowed precise quantification of the effects of the individual genes. Although partial resistance generally is effective to all genotypes of the pathogen species, the NILs demonstrated that individual QTLs may be effective to one but not to another strain of the pathogen. The NILs also allowed determining the precise position of one of the QTLs. This offers good perspectives for cloning and sequencing a gene for partial resistance, and hence, understanding its role in plant defence.
Titel proefschrift: "Genetic architecture of basal resistance of barley to Puccinia hordei"