RELATIONSHIPS AMONG CICHORIUM SPECIES AND RELATED GENERA AS DETERMINED BY ANALYSIS OF MITOCHONDRIAL RFLPS

Mitochondrial DNA polymorphism was employed to assess cytoplasmic dive rsity among cytoypes of the genus Cichorium and related genera of the tribe Lactuceae (Asteraceae). Hybridization patterns of total DNA usin g six restriction enzymes and five heterologous mtDNA probes were exam ined. From estimates of mtDNA diversity, Cichorium spinosum appeared a s an ecotype of C. intybus rather than a separate species. Interspecif ic mtDNA polymorphism in the genus Cichorium was higher than that obse rved in Cicerbita Crepis, Lactuca and Tragopogon. Molecular data seeme d to indicate that Catananche is very distant from the other genera ex amined. Intergeneric comparisons allowed the clustering of Cicerbita, Lactuca and Cichorium, genera which belong to different subtribes. How ever, further molecular investigations on a larger number of genera ar e needed to clarify the relationships among genera within and between subtribes of the tribe Lactuceae.