Pea genes associated with non-host disease resistance to Fusarium are also active in race-specific disease resistance to Pseudomonas

Abstract

A given plant species is able to resist most of the potentially pathogenic microorganisms with which it comes in contact. This phenomenon, known as non-host resistance, can be overcome only by a very small number of ‘true pathogens’ which can use that plant as a host. In some cases, plants have developed mechanisms for overcoming infection by specific races or strains of a true pathogen. This race-specific resistance can be easily manipulated into agronomically important cultivars by plant breeders. We have previously described nine cDNA clones which represent pea genes active during non-host resistance against the fungus Fusarium solani f. sp. phaseoli. In the present work, we have used these cDNAs as probes to compare non-host resistance with race-specific responses of peas against three races of Pseudomonas syringae pv. pisi. Five of the genes most active during non-host resistance were also active in direct correlation with the phenotypic expression of resistance in race-specific reactions of five differential pea cultivars against three races of Pseudomonas syringae pv. pisi.