IMPROVED MICROSATELLITE MARKERS FOR QUINCE (CYDONIA OBLONGA) GENETIC ANALYSIS
The USDA National Clonal Germplasm Repository (NCGR) maintains a diverse living collection of 149 European quince (Cydonia oblonga) individuals with origins from 16 countries. The collection is represented by one tree per accession on a 0.5-ha orchard in Corvallis, Oregon, USA. We previously used nine apple-derived simple sequence repeat (SSR) primer pairs to determine genetic relationships in 92 European quince clones, but were unable to differentiate several groups of accessions. In this study, we replaced four of the less informative SSRs with four SSRs reported to amplify at least four alleles. This new fingerprinting set improved the power of differentiation, was amplified in two multiplex PCR reactions and was used to identify 106 European and four Chinese (Pseudocydonia sinensis) quince accessions. Some previously suspected synonyms were confirmed including several clones identical to the Quince A rootstock, cultivars that grouped with Portugal, and a Meechs Prolific/Bourgault group. Unlike the previous SSR set, this improved panel distinguished a Tevloskaya seedling from the Quince A group. Gamboa is the Portuguese cultivar known as Portugal elsewhere, and their SSR fingerprints were identical. Champion, Smyrna and Van Deman at NCGR had the same fingerprint as Portugal and are likely mislabeled. Lisle from a nursery source had the same fingerprint as Pineapple. Assorted seedlings and clones from Bulgaria formed a clade, and other seedlings from the same seed lot grouped close to each other and to their parent cultivar. Several quince cultivars have phenotypes consistent with putative polyploidy such as very large fruit and very large and thick leaves. However, flow cytometry showed all NCGR quince accessions to be diploid. The SSR fingerprints revealed large genetic diversity in the USDA Cydonia genebank and will be very useful management tools for eliminating mislabeled and redundant accessions.
Bassil, N., Nyberg, A., Postman, J. and Kim, Y.K. (2015). IMPROVED MICROSATELLITE MARKERS FOR QUINCE (CYDONIA OBLONGA) GENETIC ANALYSIS. Acta Hortic. 1094, 57-65
Pseudocydonia sinensis, fingerprint, Chinese quince, simple sequence repeats (SSRs), flow cytometry, ploidy