Evaluation location: Oregon, United States
In this study, ten EST-SSRs previously isolated from Pyrus GenBank sequences were used to identify 81 P. communis, 13 P. pyrifolia and 20 P. ussuriensis or P. ?bretschneideri accessions. Cross-transference of these EST-SSRs was high in these species. PYC-008 and PYC-004 were the least informative SSRs in each of the pear species and were monomorphic in P. pyrifolia while PYC-013, PYC-002 and PYC-009b were the most informative in all species. EST-SSRs were very valuable for identification of incorrectly identified accessions, failed grafts and sets of synonyms in each of the species. Unsuspected relationships were uncovered, including a parental relationship between `Anjou? and `Farmingdale?, a clonal relationship between `Berger? and `Bartlett?, and a very close relationship between `Beurre Superfin? and `Doyenne du Comice?. One SSR marker was different in one of three sports of `Doyenne du Comice? (`Doyenne du Comice Crimson Gem?) and in one of two sports of `Anjou? (`Gebhard Red? red skin sport of `Anjou?). High cross-transference of EST-SSRs in Pyrus species is very valuable for germplasm management in such a highly diverse collection as found at the NCGR Pyrus genebank in Corvallis, OR. The results of this study were published in Genetic Resources and Crop Evolution 57:357-370.