Identification and mapping ofRpi-blb4in diploid wild potato speciesSolanum bulbocastanum

Abstract

AbstractMore than 170 years after causing the potato famine in Ireland, late blight is still considered one of the most devastating crop diseases. Commercial potato breeding efforts depend on natural sources of resistance to protect crops from the rapidly evolving late blight pathogen,Phytophthora infestans. We have identified and mapped a novel broad-spectrum disease resistance gene effective againstP. infestansfrom the wild, diploid potato speciesSolanum bulbocastanum. Diagnostic resistance gene enrichment sequencing (dRenSeq) was used to confirm the uniqueness of the identified resistance. RenSeq and GenSeq-based mapping of the resistance, referred to asRpi-blb4, alongside recombinant screening, positioned the locus responsible for the resistance to potato Chromosome 5. The interval spans approximately 2.3 MB and corresponds to the DM reference genome positions of 11.25 and 13.56 Mb.