A metapopulation framework for ex situ c onservation of the endangered Serbian spruce

The conservation of Serbian spruce ( Picea omorika (Pančić) Purk.), a rare, protected, and internationally recognised endangered species, is an important responsibility at both local and global levels. Along with numerous, mostly less successful attempts at in situ conservation, the development of effective ex situ conservation measures has become a priority for safeguarding this species. This study introduces a novel metapopulation-based approach for designing ex situ conservation plantations, applied for the first time in Serbian spruce, through the establishment of three plantations containing 70 half-sib lines representing seven endangered natural populations. The planting schemes are based on the concept of metapopulation structure, taking into account previous knowledge of genetic variability, population fragmentation, and patterns of gene flow in this species. Such an arrangement of populations and half-sib lines is expected to ensure not only the preservation of individual genotypes but also the maintenance of evolutionary processes characteristic of the natural range of Serbian spruce. At the same time, plantations organised in this way can serve multiple functions, including genetic resource conservation, progeny testing, future production of reproductive material, and potential application in breeding programmes. The metapopulation structure is expected to support these functions while reducing the negative impacts of environmental variability and climate change. The presented planting schemes provide a practical framework for the long-term ex situ conservation of Serbian spruce and a basis for future research on the adaptive potential, genetic stability, and reproductive biology of this endangered species.