ARS | Publication request: Retrospective view of North American potato breeding in the 20th and 21st century

Submitted to: Plant and Animal Genome Conference
Publication Type: Abstract Only
Publication Acceptance Date: January 9, 2013
Publication Date: January 12, 2013
Citation: Hirsch, C.N., Hirsch, C.D., Felcher, K., Coombs, J., Zarka, D., Van Deynze, A., De Jong, W., Veileux, R., Jansky, S.H., Bethke, P.C. 2013. Retrospective view of North American potato breeding in the 20th and 21st century [abstract]. Plant and Animal Genome Conference. Paper No. W695.

Technical Abstract: Cultivated potato (Solanum tuberosum Group Tuberosum), a vegetatively propagated autotetraploid, has been bred for a broad range or market classes. Breeding efforts have relied almost entirely on phenotypic selection using intra- and inter-market class crosses along with introgressions from wild Solanum species. To retrospectively explore the history of potato breeding at the genome level, a 250 clone panel with release dates ranging from 1857 to 2011 was genotyped with the SolCAP 8300 Infinium SNP chip. Population structure analysis identified four subpopulations within the panel, with the cultivated potato clones grouping together. Pair-wise kinship estimates revealed clear separation of the market classes and three distinct sub-groups of chip processing clones. The chip processing market class, for which wild species introgressions are commonly used to introduce disease resistance and market quality traits, had the highest average percent heterozygosity (59.01%) while the average in all cultivated potato was 56.13%. Through modern breeding efforts there has been minimal change in percent heterozygosity or the frequency of homozygous, single dose, and duplex loci suggesting that sufficient heterozygosity was achieved prior to formal breeding efforts in the mid-1800s. Phenotypic evaluation of the panel revealed diversification between market classes for traits under selective pressure, such as tuber sucrose in chip processing clones. Within market class improvement in historical breeding efforts was evident, such as chip color in chip processing clones. While diversification and improvement has occurred through phenotypic selection, understanding the genetic basis of traits will allow for more rapid improvement to occur in potato breeding.