ARS | Publication request: Mapping Malus sieversii: A valuable genetic resource for apple breeding

Submitted to: Plant and Animal Genome Conference Proceedings
Publication Type: Abstract Only
Publication Acceptance Date: December 1, 2009
Publication Date: January 15, 2009
Citation: Lalli, D., Wisniewski, M.E., Norelli, J.L., Malnoy, M., Pindo, M., Fazio, G., Forsline, P.L., Aldwinckle, H., Gardiner, S., Chagne, D. 2009. Mapping Malus sieversii: A Valuable Genetic Resource for Apple Breeding. Plant and Animal Genome Conference Proceedings. Abstract. p. XVIII.

Technical Abstract: The USDA-ARS Plant Genetic Resources Unit has established a collection of Malus from around the world in order to preserve and develop genetic resources important to the apple industry. Among this collection is Malus sieversii, the main progenitor of the domestic apple, collected from Central Asia (Khazakhstan). To enable QTL analysis for important traits in M. sieversii, we have undertaken the construction of a genetic framework map for the family (F1) GMAL4593 (‘Royal Gala’ X M. sieversii PI 631981 [GMAL 4448]). One-hundred-ninety progeny were analyzed using Joinmap® 3.0 for an outbreeder full-sib family population type. Of 97 SSR primer combinations screened, 51 SSRs were polymorphic within the family. Thirty-two segregated in both M. sieversii (MS) and ‘Royal Gala’ (RG), 6 segregated in MS only and 13 in RG only. Additionally, 287 SNPs were screened in a subset (96) of the population. Ninety-nine SNPs were not informative for mapping in this population and 179 were mapped using Joinmap. Fifteen of the SNPs segregated in both MS and RG, 139 with RG only and 25 with MS only. The current ‘Royal Gala’ map consists of 163 molecular markers (129 SNPs and 34 SSRs) assigned to 16 linkage groups and the MS map consists of 46 molecular markers (26 SNPs and 20 SSRs) assigned to 13 linkage groups. Additional markers (SSR and SNP) are being added. An initial phenotyping of the family for fire blight resistance has been conducted and the data is currently being subjected to QTL analysis.