Potato late blight field resistance from QTL dPI09c is conferred by the NB-LRR gene R8

• Published in: Journal of experimental botany 2018-03, Vol.69 (7), p.1545-1555
• Main Authors: Jiang, Rui, Li, Jingcai, Tian, Zhendong, Du, Juan, Armstrong, Miles, Baker, Katie, Tze-Yin Lim, Joanne, Vossen, Jack H, He, Huan, Portal, Leticia, Zhou, Jun, Bonierbale, Merideth, Hein, Ingo, Lindqvist-Kreuze, Hannele, Xie, Conghua
• Format: Article
• Language: English
• Subjects: Base Sequence; Chromosome Mapping; Disease Resistance - genetics; dRenSeq; field resistance; late blight; map-based cloning; Phytophthora infestans - physiology; Plant Diseases - genetics; Plant Diseases - microbiology; Plant Proteins - genetics; Plant Proteins - metabolism; potato; Quantitative Trait Loci; R gene; Research Papers; Sequence Alignment; Solanum tuberosum - genetics; Solanum tuberosum - microbiology
• ISSN: 0022-0957; 1460-2431
• DOI: 10.1093/jxb/ery021

Using genetics, genomics, and diagnostic RenSeq, we demonstrate that the major NB-LRR gene R8 explains the field resistance against potato late blight in the QTL dPI09c Abstract Following the often short-lived protection that major nucleotide binding, leucine-rich-repeat (NB-LRR) resistance genes offer against the potato pathogen Phytophthora infestans, field resistance was thought to provide a more durable alternative to prevent late blight disease. We previously identified the QTL dPI09c on potato chromosome 9 as a more durable field resistance source against late blight. Here, the resistance QTL was fine-mapped to a 186 kb region. The interval corresponds to a larger, 389 kb, genomic region in the potato reference genome of Solanum tuberosum Group Phureja doubled monoploid clone DM1-3 (DM) and from which functional NB-LRRs R8, R9a, Rpi-moc1, and Rpi_vnt1 have arisen independently in wild species. dRenSeq analysis of parental clones alongside resistant and susceptible bulks of the segregating population B3C1HP showed full sequence representation of R8. This was independently validated using long-range PCR and screening of a bespoke bacterial artificial chromosome library. The latter enabled a comparative analysis of the sequence variation in this locus in diverse Solanaceae. We reveal for the first time that broad spectrum and durable field resistance against P. infestans is conferred by the NB-LRR gene R8, which is thought to provide narrow spectrum race-specific resistance.