Genetic variability and degradation drivers for conserving and managing oak populations at the landscape of outstanding features "Kosmaj" (Serbia)

Abstract

Identification and quantification of the factors that influence genetic diversity is particularly important for the representatives of the genus Quercus L. In this genus, the characterization of the genetic diversity correlations can serve as a basis for predictive models of its distribution. The adaptive and neutral genetic variability of four autochthonous oak species (Quercus petraea (Matt.) Liebl. – sessile oak, Q. pubescens Willd. – pubescent oak, Q. frainetto Ten. – Hungarian oak, Q. cerris L. – Turkey oak) was studied at the Landscape of Outstanding Features (LOF) "Kosmaj" in Serbia. This study aimed to test to which degree the inter- and intraspecific genetic variability of oaks is the result of the genotype influence, local habitat conditions, environmental factors, population management practices, and the historical processes that the analyzed populations have gone through. In total, 247 individuals of the four selected oak species were investigated. Adaptive variability was studied using geometric morphometric methods (landmarks and outlines), and neutral variability using nuclear microsatellites (nSSRs). The results showed that the adaptive variability of oaks at the LOF "Kosmaj" is related to habitat characteristics, environmental conditions, and oak population management practices, while neutral variability analysis showed relatively high genetic diversity levels of all studied oak species. The consistency of the results obtained using adaptive and neutral genetic markers, and the consistency of the obtained results with previously published data on genetic variability of oaks was also observed. The results suggest that the effective conservation of oak genetic resources at the LOF "Kosmaj" requires coordinated efforts of the forestry, environmental and nature protection sectors. An important goal is the determination of priority species, populations and areas for the conservation of oak genetic resources in the form of in situ conservation units and ex situ methods, within a coherent program and in accordance with national policies and the biological capabilities of each species.