Morphological and phytochemical variation, genetic structure and phenology in an introgressive hybrid swarm of Senecio hercynicus and S. ovatus (Compositae, Senecioneae)

Abstract

Random amplified polymorphic DNA (RAPD) fingerprinting was used to study species boundaries in six closely related NE Turkish Lilium (Liliaceae) taxa of the section Liriotypus. The investigated taxa were L. ciliatum, L. akkusianum, L. ponticum, L. kesselringianum, L. armenum, and L. szovitsianum. Of the 108 primers screened, 11 provided polymorphic and reproducible bands. A total of 93 polymorphic bands were scored for 122 individuals from 18 populations of the six Lilium taxa and principle coordinate analysis and neighbour-joining cluster analysis based on these RAPD profiles were performed. The results demonstrate a clear distinction between the two species L. ciliatum and L. akkusianum, and the other four species. While populations of the two species groups are found to be allopatrically distributed, the two species groups overlap in their geographical ranges. Analysis of molecular variance (AMOVA) indicated that nearly half of the total molecular variance is found within the individual populations and that the molecular variance among species is as high as the variance within the individual species, indicating that genetic differentiation of the species is rather weak.