Cloning candidate genes for a broad-spectrum resistance QTL against Phytophthora capsici in pepper
Résumé
Late blight, caused by the pathogen Phytophthora spp. (Oomycete), is one of the most damaging diseases of Solanaceae. The deployment of resistant varieties is the most effective, economical and environmentally safe control of Phytophthora. Contrary to monogenic resistances that are easily overcome by the pathogen, polygenic resistances generally confer a durable control of disease severity. However, their molecular basis remains unknown since no resistance QTl to Phytophthora has ever been characterized. Phy-P5, the major effect Phytophthora capsici resistance QTl in pepper, has been mapped on the chromosome P5. It was detected in 3 pepper accessions and displayed a broad-spectrum resistance to several P. capsici isolates. We airn to determine the molecular basis of Phy-PS by isolating the responsible gene deploying a positional cloninq strategy.