ARS | Publication request: LATE BLIGHT RESISTANCE MAPPING IN THE WILD POTATO SOLANUM PIURANA CLADE

Submitted to: Plant and Animal Genome Conference
Publication Type: Abstract Only
Publication Acceptance Date: July 15, 2003
Publication Date: January 15, 2004
Citation: Villamon, F., Spooner, D.M., Orrillo, M., Mihovilovich, E., Perez, W., Wulff, E., Bonierbale, M. 2004. Late blight resistance mapping in the wild potato solanum piurana clade[abstract]. Plant and Animal Genome Conference. p. 215.

Technical Abstract: Several tuber-bearing potato species have been used as sources of resistance to P. infestans and researchers have continuously dealt with the premise that different sources harbor different types of resistance. This study examines a group of Solanum species from a sister clade of cultivated potato that has not yet been used in breeding, under the hypothesis that it may have developed novel resistance during its separate evolution under endemic conditions of the disease. The 'Solanum Piurana' clade was recently described through chloroplast DNA restriction site data to be comprised of members of series Piurana and species from other recognized series. Despite prior publication that series Piurana did not carry resistance, preliminary screening in our laboratories showed a range of late blight reactions from extremely susceptible to extremely resistant. Seven heterogenous accessions of two species, S. chomatophilum (chm) and S. paucissectum (pcs) were evaluated under natural disease pressure in two locations in Peru, and in detached leaf assays using isolates from potato and from the resistance donor. An interspecific backcross progeny was developed between a resistant and a susceptible individual (pcs/chm//chm). A framework map of 60 RFLP markers was constructed from homeologous tomato to compare the positions of QTL and R-gene loci from pcs with those already published for other clades. Marker density was increased with mapped SSRs to describe factors governing quantitative and qualitative resistance. Significant effects have been located on the short arms of both chromosomes 5 and 11, the latter explaining a difference of 500 AUDPC units.