Unravelling some factors affecting sexual reproduction in rock-specialist shrub: Insight from an endemic Daphne arbuscula (Thymelaeaceae).

The role of endemic species in global biodiversity is pivotal, and understanding their biology and ecology is imperative for their fitness and long-term survival, particularly in the face of ongoing climatic oscillations. Our primary goal was to investigate the sexual reproduction level of the endangered Western Carpathian endemic Daphne arbuscula (Thymelaeaceae), which inhabits extreme rocky habitats, and to comprehend the influence of specific factors on its reproductive success. We conducted the research across four populations, varying in size and environmental conditions. Over two years, we monitored flower and fruit production, analyzed genetic variability within and among populations, and studied pollination mechanisms. Daphne arbuscula proved to be strictly self-incompatible, with significant variations in flower and fruit production among populations and seasons. The average fruit production percentage consistently remained below 50% across populations, indicating challenges in sexual reproduction. Cold and harsh weather during the reproductive phase had a substantial negative impact on sexual reproduction efficacy, leading to decreased fruit production. Nevertheless, several individuals in sheltered microhabitats displayed significantly higher fruit production, ranging from 60% to 83%, emphasizing the critical role of microhabitat heterogeneity in sustaining sexual reproduction in this species. We found no pronounced differences in genetic diversity within or among populations, suggesting that genetic factors may not critically influence the reproductive success of this endemic species. The implications of our findings might be of paramount importance for the long-term survival of D. arbuscula and offer valuable insights for the development of effective conservation strategies for this species.

Vegetation affinity of species Typha shuttleworthii in the western part of the Carpathians, with Typhetum shuttleworthii as a new association to Slovakia.

Typha shuttleworthii (Shuttleworth's bulrush) is a rare species throughout its distribution range including Carpathians. However, a substantial increase in its finds has been noticed in the last twenty years. This study summarises the present knowledge and brings new data on vegetation with T. shuttleworthii occurrence from the western part of the Carpathians (Czech Republic, Slovakia, Poland and Ukraine) with the aims of evaluating the phytosociological affinity of this species and providing new information about the ecology of the relevant plant communities. We found that T. shuttleworthii mainly occurred in marsh vegetation (the Phragmito-Magnocaricetea class) including the Typhetum shuttleworthii association. Some plots also corresponded to transitional stands between marshes and wet meadows of the Molinio-Arrhenatheretea class (Molinietalia caeruleae order). Moisture and soil reaction were identified as principal factors responsible for variation in species composition of the vegetation. Typhetum shuttleworthii was recognised as new for the territory of Slovakia and confirmed in all other countries, Czech Republic, Poland and Ukraine. Our results could contribute to better preservation of the species and its habitats and thus be very important for practical nature conservation.