Morphologically defined Cichorium (Asteraceae) species reflect lineages based on chloroplast and nuclear (ITS) DNA data

Cichorium spinosum and C. bottae are morphologically well diagnosed species. The remaining four species in the genus, C. intybus, C. endivia, C. pumilum, and C. calvum, are usually difficult to distinguish because they differ primarily in quantitative characters. However, our study indicates, that these species are not intermixed in a multivariate analysis of morphological characters. A cladistic analysis of restriction fragment length polymorphisms and trnL-trnF sequences of the chloroplast genome and nuclear ribosomal DNA sequence data obtained from the six Cichorium species and nine possible outgroup genera indicates that 1) Cichorium has an isolated position within the tribe Lactuceae, 2) C. bottae is sister to all other species of Cichorium, and 3) the remaining species are divided into two main clades, one consisting of C. calvum, C. pumilum, and C. endivia and the other consisting of C. intybus and C. spinosum.