Assessment of European pear (Pyrus communis L.) genetic resources in Bosnia and Herzegovina using microsatellite markers

The pear germplasm of Bosnia and Herzegovina (B&H) consists of cultivars introduced both from Asia Minor and Western Europe and until now has not been adequately investigated. In this study, 64 pear accessions, 27 traditional B&H cultivars and 9 international reference cultivars, maintained at the ex situ apple and pear collection Srebrenik (Northeast Bosnia), together with 28 presumed traditional pear accessions collected from a number of backyards and small farms in Sarajevo, were assessed using 13 microsatellite markers. Of the thirteen primer pairs which were used, two primer pairs (CH02C06 and CH05e03) either did not amplify or produced poor amplification in our samples. Eleven remaining primer pairs successfully amplified 159 distinct alleles, or on average 14.5 alleles per locus. Presence of a third allele was detected for 31% of the analyzed accessions. After elimination of duplicates, 53 pear genotypes remained for further investigation. Analysis of molecular variance (AMOVA) revealed a significant genetic differentiation between both groups of traditional pear accessions and the international reference cultivars, but found no significant differentiation among traditional B&H cultivars from Srebrenik and accessions from Sarajevo. Factorial correspondence analysis (FCA) confirmed results obtained by AMOVA. Bayesian method and admixture analysis of the allele frequency allowed for classification of all accessions analyzed into five RPPs. Most (78%) of the international reference cultivars grouped in RPP2, whereas traditional B&H cultivars from the ex situ collection at Srebrenik and accessions from Sarajevo grouped in all five RPPs. None of the international reference cultivars grouped in either RPP1 or RPP5. Analyses of molecular variance detected significant differentiation among RPPs (f(CT) = 0.082; P < 0.001). Results of various analyses used, indicate that many traditional B&H cultivars from Srebrenik and Sarajevo represent an interesting genetic resource. (c) 2013 Elsevier B.V. All rights reserved.