Contemporary inter-specific hybridization between Cirsium aduncum and C. haussknechtii (Asteraceae): Evidence from molecular and morphological data

Abstract

Cirsium aduncum Fisch. & C.A.Mey. Ex DC. and C. haussknechtii Boiss., (Asteraceae) are important medicinal plant species that grow in different geographical regions of Iran. We had no knowledge about population genetic structure, intra-specific and inter-specific gene flow and the presence of hybrid zone for this two species in Iran. Therefore, in order to provide data for conservation of these two medicinally important species, the population genetic analysis and morphometric studies were performed in 18 geographical populations of these species. ANOVA and MDS analyses revealed significant morphological difference among the studied populations in either species, while MDS plot showed morphological overlap in plants of these two species. AMOVA test revealed significant genetic difference among the studied populations. Mantel test showed positive significant correlation between genetic and geographical distances and the occurrence of isolation by distance. Population assignment test and STRUCTURE plot of genetic data revealed inter-specific introgression between these species.