PHYLOGENY AND SPECIES RELATIONSHIPS IN JASIONE (CAMPANULACEAE) WITH EMPHASIS ON THE ‘MONTANA-COMPLEX’

Abstract

The evolutionary relationships of several, mainly Iberian, Jasione taxa (Campanulaceae) were investigated using molecular data. A parsimony analysis of the internal transcribed spacer (ITS) region of nuclear ribosomal DNA was partially successful in elucidating some interspecific alliances. One of the main clades included three morphologically rather disparate species from S Spain and Morocco which might indicate that these areas were refugia during the last glaciations. The fact that most of the other taxa fell in a large polytomy suggests a recent origin of these species. Amplified fragment length polymorphisms (AFLPs) were analysed for a larger sample set of two taxa from within the ITS polytomy to assess the partition of genetic variation between and within populations. All the British accessions named J. montana var. montana were found to be close to those so-named from Spain. However, individual accessions of J. montana var. montana from Argyll (Scotland), Devon (SW England) and the Shetland Islands proved to be genetically different from each other. This might suggest a low level of genetic diversification from a common progenitor due to a rapid northward migration. It is proposed that J. montana var. bracteosa and J. maritima var. sabularia merit recognition at higher rank. The possibility that J. montana vars gracilis and latifolia are mere repetitive segregants of J. montana var. montana is considered.