Genetic variation and performance of the alpine plant species Dianthus callizonus differ in two elevational zones of the Carpathians

In this investigation, we studied whether genetic variation and performance of the alpine plant species Dianthus callizonus differ between two different elevational zones of the southern Carpathians in Romania. We analysed 17 populations of the species from two study regions at 1700 and 2100 m above sea level in the Piatra Craiului Mountains applying AFLP analyses and morphological measurements. Following our results, population size differed between the two study regions and genetic variation within populations depended on population size. Population size and genetic variation within populations were higher in the study region located at 1700 m. By contrast, genetic variation between populations was nearly twice as large in the study region located at 2100 m. In a Mantel test, genetic and geographic distances between populations were clearly correlated. Moreover, individuals from the study region at 2100 m were significantly smaller, had fewer shoots, fewer flowers per shoot and produced seeds with a lower seed mass than individuals from the study region at 1700 m. The results of our study support the observation that changing environmental conditions along elevational gradients in mountain regions affect population size, genetic variation and performance of alpine plant species from different elevational zones, which should be considered in plant conservation