Polymorphism in Syringa rDNA regions assessed by PCR technique

The Syringa genus is characterizedby a multiplicity of forms. Its chief asset is the ornamental value of thousands of accessions, species or hybrids. From a phylogenetic point of view the genus is difficult in an explicit classification due to its frequently complex genome. The aim of this study was to determine the possibility for the identification of genotypic diversity and genetic relationships in the nrDNA sequence of some selected Syringa accessions – part of a collection of the Dendrological Garden in Przelewice (Poland). For this purpose, the PCR technique together with a combination of various ‘universal’ primers designed for the nrDNA sequence analysis were employed. Fourteen Syringa accessions: Syringa × chinensis Willd., S. × prestoniae Mc Kelv., S. × prestoniae ‘Telimena’, S. × prestoniae ‘Jaga’, S. × prestoniae ‘Basia’, S. meyeri ‘Palibin’, S. vulgaris ‘Miss Ellen Willmott’, S. vulgaris, S. vulgaris ‘Jules Simon’, S. vulgaris ‘Katherine Havemeyer’, S. vulgaris ‘Krasawica Moskvy’, S. vulgaris ‘Mirabeau’, S. vulgaris ‘Madame Lemoine’ and S. vulgaris ‘Niebo Moskvy’ made up the research material. In the conducted amplifications, genetic profiles were obtained for 14 combinations among the 25 combinations of different pairs of primers used. The nrDNA templates coding the small subunit (SSU), 5.8S subunit andITS1, ITS2 andIGS sequences were amplified. In PCR reactions a total of 33 PCR products were generated, of which 21 (64%) products were polymorphic, 6 (18%) monomorphic and6 (18%) were genotype-specific. For the lilac accessions examined246 amplicons were generated from ~230 to ~1100 bp in length. The analysis of both the dendrogram and the genetic similarity matrix revealedlow diversity between the examinedaccessions. For most they rangedfrom 70 to 80%, andthe greatest diversity (87%) was foundbetween the S. × prestoniae: ‘Basia’ and‘Telimena’ accessions, while the lowest (57%) was observed between S. vulgaris ‘Katherine Havermeyer’ and S. × chinensis.