Abstract
Intergenic spacers of the rRNA genes of three species of theCynareae tribe:Cynara cardunculus subsp.scolymus (artichoke),Onopordum acanthium, andO. illyricum were cloned in the plasmid pGEM-7zf(+). Detailed restriction mapping and partial sequencing of the IGSs were carried out. The structural analysis showed a clear diversity betweenCynara andOnopordum, while a high degree of homology was found between the twoOnopordum spp. In all three species a fragment of about 450 bp from the 5′ end of 18S to the Acc I site with a high sequence homology was present. Nucleotide sequences upstream from the above mentioned Acc I site show a gradual decrease of homology betweenCynara andOnopordum.
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Tucci, G., Simeone, M.C., Gregori, C. et al. Intergenic spacers of rRNA genes in three species of theCynareae (Asteraceae). Pl Syst Evol 190, 187–193 (1994). https://doi.org/10.1007/BF00986192
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DOI: https://doi.org/10.1007/BF00986192