Utility of Standard Microsatellite Markers for Identification of Asian Pears (Pyrus spp.)

Pear (Pyrus spp.) is one of the most economically important temperate fruit species along with grape and apple and about 21 primary species proposed by Challice and Westwood (1973) are widely recognized by the taxonomists. Establishing germplasm collection is ongoing work to avoid loss of biological diversity and to use for breeding. However, genetic resources from germplasm collection is unwilling to utilize due to mis-identification caused by lack of accurate identifying marker. To correct the problem, DNA-based molecular markers were developed and utilized for germplasm management. Those of DNA-based molecular markers, microsatellite marker is one of the most widely used. Especially in fruit tree germplasm collections belong to germplasm researching institute such as The European Cooperative Programme for Plant Genetic Resources (ECPGR), National Fruit Collection (NFC), and National Clonal Germplasm Repository use microsatellite marker to manage germplasm collection. The objective of the study was identifying Asian pear accessions with 12 microsatellite markers to maintain pear germplasm collection. Fifty-one Asian pear accessions, two primary pears, and P. communis pear were analyzed with twelve microsatellite markers proven polymorphism. P. communis was out-grouped, the other accessions were distributed into two groups. The first group consisted of P. bretschneideri and P. ussuriensis. The second group was consisted P. pyrifolia including ‘Danbae’ (P. pyrifolia Nakai x P. ussuriensis Maxim.). Genetically related accessions which share crossing parents was placed in each small groups of the second group. Result from the dendrogram, the reliability of the 12 microsatellite markers to manage Asian pear germplasm was proven.