Submitted to: Acta Horticulturae
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: February 1, 2011
Publication Date: October 31, 2011
Citation: Bassil, N.V., Postman, J.D., Hummer, K.E., Sugar, D., Mota, J., Williams, R. 2011. Quince (Cydonia oblonga) genetic relationships determined using microsatellite markers. Acta Horticulturae. 909:75-83. Interpretive Summary: Quince is a fruit crop related to apples and pears that originated in Central Asia. It has been cultivated for thousands of years in that part of the world for its fragrant fruit. Quince is also used as a rootstock for grafting pears when a dwarf pear tree is desired. The USDA Agricultural Research Service maintains a diverse living collection of quince trees with origins in more than 15 countries at the National Clonal Germplasm Repository, a genebank in Corvallis, Oregon. DNA fingerprinting techniques that have been used to identify different apple and pear cultivars were applied to quince, and several of the same DNA markers were also useful for identifying quince cultivars. More than 80 different quince cultivars could be differentiated from each other using 9 different markers. Several different quince cultivars from different countries and with different names had identical DNA fingerprints, suggesting that they are synonyms. Turkey is a place where quince is widely grown and where many different cultivars originated. Some large fruited quince cultivars from other countries including Portugal, Ukraine and the U.S. had fingerprints very similar to large-fruited Turkish cultivars, suggesting that they may have originated from Turkish germplasm. A few unique quince cultivars could not be separated from each other, suggesting that some additional refinements should be made to the fingerprinting technique. This study represents the first report on genetic identity evaluation of quince from such diverse origins.
Technical Abstract: The quince, Cydonia oblonga Mill., belongs to a monotypic genus and is a close relative of apple (Malus) and pear (Pyrus) in the Rosaceae family. It has been cultivated for thousands of years in central Asia and the Middle East for its fruit, and for hundreds of years as a dwarfing rootstock for pear. The USDA-ARS National Clonal Germplasm Repository in Corvallis, Oregon has assembled a diverse living collection of Cydonia genotypes originating from more than 15 countries, and maintained as self-rooted orchard trees. We evaluated 24 apple SSR primer pairs that also amplify in pear for cross-transference to 45 diverse quince accessions from the Corvallis collection. Nine apple primer pairs that appeared polymorphic in quince were selected and used to evaluate genetic relationships among 92 quince genotypes and 3 intergeneric pear x quince hybrids (×Pyronia veitchii (Trab.) Guillaumin). The quince accessions proved to be very diverse, with only 6 sets of synonyms in addition to a group of 12 clones that could not be differentiated. ‘Meech’s Prolific’ and ‘Le Borgeot’ had identical fingerprints, and similar phenotypes. ‘Portugiesiche Birnquitta’, ‘Gamboa’, ‘Bereczki’, ‘Rich’ and ‘Van Deman’ also had identical fingerprints and similar phenotypes. Several large-fruited clones from Turkey grouped closely with the five “Portugal” clones and also with other large-fruited quince clones from Ukraine and USA suggesting Turkish germplasm as a possible origin for the group. Additional SSR markers may be needed for finer resolution where unique clones could not be differentiated. This study represents the first genetic identity evaluation of quince genotypes spanning much of Cydonia’s natural wild and cultivated geographic distribution.