Intraspecific variations and biological relationships of different populations of Centaurea virgata Lamark (Asteraceae) in Iran

Being a large genus in the Asteraceae family, the genus Centaurea is a complex and problematic taxon. Centaurea virgata Lamark is a widespread and invasive species of the Centaurea genus. This species is found in different regions of Iran. However, there are limited studies on this plant, especially at the morphologic and genetic level. The present study aimed to investigate the intraspecific variations of C.virgata collected from different regions of Iran based on morphological data. A morphometric study based on 27 quantitative and 28 qualitative morphological characters was carried out on 65 specimens from 31 populations. Cluster and principal coordinates analyses (PCO) of morphological characters showed that the 31 populations could be divided into three main groups and two subgroups. The analyses of variance (ANOVA) of morphological characters indicated that most of the evaluated characters were significantly different (P˂0.05) among C. virgata populations. It also demonstrated that there were not significant differences (P˂0.01) among populations of C. virgata for six morphological characters, including the width of the inflorescence leaves, inner phyllaries width, outer phyllaries width, outer phyllaries cilia length, phyllary rows number, and stamen number. It could be concluded that there is a high morphological variation among various populations of C. virgata collected from different regions of Iran. These morphological variations of C. virgata populations can be related to different ecological and environmental conditions or endogenous factors such as genetics, and the presence of adaptation mechanisms to specific situations.