Seed Regeneration in Taxus baccata: Unveiling Ecological Restrictions and Paving the Way for Future Studies

Taxus baccata, commonly known as English yew, is an evergreen tree native to regions ranging from Ireland and Sweden to Morocco, Algeria, and northern Iran. This species is of special concern due to habitat loss from human activities, including forest management, leading to declining populations. A 4-year monitoring study was conducted to investigate the factors behind the poor seed regeneration of yew. We examined seed germination, dormancy, desiccation tolerance, and seed predation as potential contributors to this issue. Our study proposed potential seed predation by frugivores and granivores, along with morphophysiological dormancy, as primary reasons for poor regeneration. Despite high seed production and seed availability in certain years, germination did not improve, likely due to the small size of the yew seed embryos, which prolongs dormancy. Yew seeds are desiccation-tolerant, water-permeable, and lack physical germination barriers, making seed predation a significant limiting factor. In conclusion, the natural regeneration of yew is hampered by potential seed predation, morphophysiological dormancy, and environmental factors such as altered temperature and rainfall patterns, which change the dormancy-breaking process. Further research is needed to quantify seed predation and explore its impact on seedling survival.