A New Pathosystem for Study on Plant-Fungal Pathogen Interaction.

Abstract

When challenged with the fungus Colletotrichum higginsianum, Arabidopsis accession Columbia plant (Col-0) developed brown necrotic lesions, including a yellow halo around the lesion. The Arabidopsis accessions showed variation in response to C. higginsianum. Arabidopsis accession Eil-0 was highly resistant to C. higginsianum. In the Eil-0 plant inoculated with the fungus, cell death did not appear as a rapid response, and the level of camalexin accumulated was low. Analyses using RNA gel blotting and cDNA microarray suggested that the defense responses against C. higginsianum occur mainly through the JA/ET-dependent pathway. Segregation analysis of progeny from crosses between Eil-0 and Col-0 plants was performed to determine the genetic basis of resistance. The resistance was dominant and seemed to be conferred by a single locus. Arabidopsis and C. higginsianum provide an excellent pathosystem for studying the molecular and cellular bases of plant-pathogen interactions