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Background and Aims Interactions between ecological factors and seed physiological responses during the establishment phase shape the distribution of plants. Yet, our understanding of the functions and evolution of early-life traits has been limited by the scarcity of large scale datasets. Here, we tested the hypothesis that the germination niche of temperate plants is shaped by their climatic requirements and phylogenetic relatedness, using germination data sourced from a comprehensive seed conservation database of the European flora (ENSCOBASE). Methods We performed a phylogenetically informed Bayesian meta-analysis of primary data, considering 18,762 germination tests of 2,418 species from laboratory experiments conducted across all European geographic regions. We tested for the interaction between species’ climatic requirements and germination responses to experimental conditions including temperature, alternating temperature, light and dormancy breaking treatments, while accounting for between-study variation related to seed sources and seed lot physiological status. Key Results Climate was a strong predictor of germination responses. In warm and seasonally dry climates the seed germination niche includes a cold-cued germination response and an inhibition determined by alternating temperature regimes and cold stratification, while in climates with high temperature seasonality opposite responses can be observed. Germination responses to scarification and light were related to seed mass, not climate. We also found a significant phylogenetic signal in the response of seeds to experimental conditions, providing evidence that the germination niche is phylogenetically constrained. Nevertheless, phylogenetically distant lineages exhibited common germination responses under similar climates. Conclusion This is the first quantitative meta-analysis of the germination niche at a continental scale. Our findings showed that the germination niche of European plants exhibit evolutionary convergence mediated by strong pressures at the macroclimatic level. In addition, our methodological approach highlighted how large datasets generated by conservation seed banking are valuable sources to address questions in plant macroecology and evolution.

To meet the international biodiversity targets of the 2011–2020 Global Strategy for Plant Conservation, it is important to assess the success of coordinated ex situ plant conservation initiatives such as the European Native Seed Conservation Network (ENSCONET), which operated during 2005–2009, and the ENSCONET Consortium, which was established in 2010. In particular, analysis of the ENSCONET database (ENSCOBASE) indicates that ex situ seed banks have been making significant progress towards meeting targets 8 (at least 75% of threatened plant species in ex situ collections, preferably in the country of origin, and at least 20% available for recovery and restoration programmes) and 9 (70% of the genetic diversity of crops, including their wild relatives and other socio-economically valuable plant species, conserved, while respecting, preserving and maintaining associated indigenous and local knowledge) for native European species. However, the infraspecific diversity of threatened species stored in ENSCONET seed banks needs to be increased to meet research and conservation objectives.

The contribution of the European Native Seed Conservation Network (ENSCONET, 2004(ENSCONET, -2009 and the ENSCONET Consortium (since 2010) towards meeting the 2020 Global Strategy for Plant Conservation (GSPC) target 8 was assessed in 2017. While the outcome was positive (62.7% of European threatened species already conserved ex situ in seed banks), the analysis showed that it was essential to provide guidance on which European native threatened species should be collected as a priority if the target was to be reached by 2020. In this paper we present a priority-setting method and its result, designed to guide collecting strategies across Europe to meet the 2020 GSPC target 8. The result of our study is a country-based checklist of European threatened taxa to be collected and stored ex situ across the seed banks of the ENSCONET Consortium by 2020. After discussing the results of the applied method, the ENSCONET Consortium Steering Committee has identified some key action points to support the implementation of such a collecting strategy across Europe in order to meet the 2020 GSPC target 8 for Europe.