Quantitative Trait Loci (QTL) Analysis Reveals Both Broad-Spectrum and Isolate-Specific QTL for Scab Resistance in an Apple Progeny Challenged with Eight Isolates of Venturia inaequalis

• DOI: 10.1094/phyto.2004.94.4.370
• Publication Date: 2007-05-11T11:25:03Z
• Authors: F. Calenge; A. Faure; M. Goerre; C. Gebhardt; W. E. Van de Weg; L. Parisi; C.-E. Durel
• Keywords: Venturia inaequalis; Apple scab; Malus; Genetic Analysis; Genetic linkage

The major scab resistance gene Vf, extensively used in apple breeding programs, was recently overcome by the new races 6 and 7 of fungal pathogen Venturia inaequalis. New, more durable, genes are needed programs. F 1 progeny derived from cross between partially resistant cv. Discovery hybrid ‘TN10-8’ were inoculated greenhouse with eight isolates V. inaequalis, including able to Vf. One gene, Vg, seven quantitative trait loci (QTL) identified for these isolates. Three QTL on linkage group (LG)12, LG13, LG15 clearly isolate-specific. Another LG5 detected two LG1, LG2, LG17 most tested, but not every isolate. LG2 displayed alleles conferring different specificities. This co-localized Vr Vh8, whereas LG1 colocalized These results contribute a better understanding genetic basis inaequalis-Malus × domestica interaction.