[Plant rDNA: organisation, evolution, and using].

Ribosomal DNA comprises a considerable part of a plant genome and is organized in tandemly arranged repeats composed of conservative coding sequences for ribosomal RNA and rapidly evolving spacer elements. We determined the nucleotide sequences of intergenic spacer regions (IGS) for five species from Solanacaea family: Solanum tuberosum, Atropa belladonna, Nicotiana tabacum, N. tomentosiformis, and N. sylvestris. The detailed comparative analysis of these and some other rDNA sequences allowed us to reveal the general regularities of evolution and functional organization of the rDNA spacer region and to clarify better phylogenetic relationships between the species within Solanacea family. A large body of experimental data on the application of rDNA in plant breeding, taxonomical studies and biotechnology are provided and discussed.