Identification of Colletotrichum higginsianum Resistance Loci in Arabidopsis thaliana

Abstract

A collection of 40 ecotypes of Arabidopsis varied in their responses to infection by C. higginsianum. Analyses suggested that the hypersensitive response and reactive oxygen species are important in a defense response. Crosses between the resistant and susceptible ecotypes suggested that the resistance was dominant and was conferred by a single locus, which we named RCH (for Recognition of Colletotrichum higginsianum). We mapped the RCH locus in several resistant ecotypes by using PCR-based microsatellite and amplified polymorphic sequence genetic markers. Our results indicated that the RCH1 locus was linked to the SSLP marker nga8, located at the chromosome 4. In addition, it is shown that Arabidopsis plants have a variety of RCH loci. Furthermore, expression analyses were performed using a microarray. In this meeting, we present expression profiles of regulatory genes in C. higginsianum-inoculation using a microarray.