rDNA Variability Assessed in PCR Reactions of Selected Accessions of Acer

The region of rDNA (SSU, 5.8S, LSU and ITS1, ITS2 spacer sequences) of fourteen Acer accessions was tested in order to determine the possibility to identify genotypic variability within a rDNA sequence. The tests were performed using the PCR technique and a set of combination of several pairs of ‘universal’ primers designed to amplify rDNA sequences. ‘Universal’ primers were selected in such a way as to make the rDNA regions flanking possible in cases where a smaller or larger scope of variability was expected. Thus, within SSU or LSU sequences, monomorphic PCR products were amplified for the tested Acer accessions. Within the ITS sequence, a greater scope of variability was found. This was manifested by the presence of several additional PCR products in the genetic profiles of the tested Acer accessions. The range of their length relative to the ITS region or ITS1, ITS2 or 5.8S corresponded separately to that described in the literature. The analysis of the topology of the constructed tree revealed the presence of two similar groups, ‘a’ and ‘b’. Cultivated varieties and one botanical variety of the Japanese maple were included respectively in these groups and the genetic similarity between the analyzed accessions ranged from 63 to 98%.