Abundance and Phenotypic Diversity of the Medicinal Sideritis Scardica Griseb. in Relation to Floristic Composition of Its Habitat in Northern Greece

Abstract

Sideritis scardica (S. scardica) is an endemic medicinal species of the Central Balkan Peninsula. The aerial parts are traditionally used in folk medicine and, therefore, have been collected extensively from natural habitats. Overexploitation in combination with climate change has resulted in severely fragmented populations. In this context, the purpose of this study was to access the abundance and phenotypic diversity of S. scardica populations in relation to plant community structure and environmental and anthropogenic factors in six mountainous areas of Northern Greece. For this reason, the floristic composition and diversity was determined by accessing the number of plant species, number of individuals per plant species, and plant cover in each study area. In addition, the soil properties of the studied areas were determined and the phenotypic diversity of S. scardica populations was accessed through the imaging of leaf and inflorescence main characteristics. As a result, 141 plant species were identified in all studied areas, while the floristic composition clearly distinguished the North-Central from the North-Eastern studied areas. S. scardica was the predominant species in the habitats where the presence of forbs was favored, while a high presence of graminoid and shrub species in the study areas depressed its presence. A high coefficient of variations was recorded among the six populations, varying from 12.2%–29.2% and 13.3%–43.1% for inflorescence and leaf traits.