Molecular Markers Analysis of Main Cultivars Relationship Between Pyrus in Xinjiang

To assess the interspecific relationships in Pyrus,eighteen samples of Pyrus were used for RAPD assay.Of the 160 random decamer oligonucleotide primers tested,twelve we selected produced abundance polymorphic products.A total of 133 products amplified from 12 primers were selected for RAPD analysis.Every primer amplified eleven products in average.Fourteen amplified products were found to be coexistence bends,relatively one hundred and nineteen (89.47%)products were polymorphic loci among 18 samples.Data were used to generate Nei's similarity coefficients and to construct dendrograms using UPGMA and NJ in the PHYLIP computer programs.Nei's similarity coefficients were between 0.5 and 0.923,and it is concluded from this study that:1) RAPD results coincided with traditional morphological taxonomy for P.sinkiangensis Yu,P.bretschneideri Rehd,P.pyrifolia Nak,P.communis L and P.ussriensis Max;2) The samples of several sports were very similar; 3) The hybrid cultivar XIN-liyihao pear and DANGSHAN-suli pear were clustered together.The hybrid cultivar XINliluhao pear and Kurle fragrant pear were clustered.The hybrid cultivar Zaosuli pear and Pingguoli pear were clustered; 4) Pingguoli pear was independent among five experimental species of Pyrus. It should be changed to a species from a cultivar; 5) The dendrograms clustered Kurle fragrant pear into P.sinkiangensis Yu.