ARS | Publication request: Resistance Gene Mining in Wild and Cultivated Potato Germplasm

Submitted to: Plant and Animal Genome Conference
Publication Type: Abstract Only
Publication Acceptance Date: November 5, 2007
Publication Date: January 12, 2010
Citation: Halterman, D.A. 2010. Resistance Gene Mining in Wild and Cultivated Potato Germplasm [abstract]. Plant and Animal Genome Conference. Paper No. W376.

Technical Abstract: A key long-term management strategy for combating potato diseases is to develop cultivars with high levels of resistance through identification and integration of major resistance (R) genes. This talk will summarize our results of cloning major R genes from potato germplasm using a candidate gene approach. The RB gene, cloned from the Mexican diploid potato species Solanum bulbocastanum, confers broad-spectrum resistance to potato late blight. We have determined the late blight resistance phenotypes of eight accessions of S. verrucosum, another wild diploid potato species, using greenhouse inoculations and discovered variability among the accessions. Transcribed orthologs of the RB gene from these eight S. verrucosum accessions were cloned using a homology-based PCR approach. Stable introduction of the RB ortholog from late blight resistant S. verrucosum into susceptible S. tuberosum confers resistance to P. infestans. We have now expanded this procedure to other wild potato species and have identified several other candidate RB orthologs. We have used a similar approach to identify and clone a putative ortholog of the tomato Verticillium wilt R gene Ve from both resistant and susceptible interspecific potato hybrids. The potential use of these sequences in marker development and molecular characterization of R proteins will be discussed.