Format: ORAL

Angelino Carta1, Efisio Mattana2, Andreas Ensslin3, Sandrine Godefroid4, Rafael Molina-Venegas5

1 University of Pisa, Pisa, Italy 2 Royal Botanic Gardens, Kew, Ardingly, UK 3 Conservatory and Botanic Garden of Geneva, Switzerland 4 Meise Botanic Garden, Meise, Belgium 5 Universidad Autónoma de Madrid, Madrid, Spain

With two in five plants facing extinction, identifying currently unsecured branches of the Tree of Life is key to prioritise future conservation efforts. Thus, phylogenetic diversity (PD) methods become crucial in designing cost-effective conservation planning for species prioritisation and prevent lineages loss. Conventional seed banking (i.e., conservation of desiccation-tolerant seeds at below-zero temperatures) is the most efficient and effective ex-situ method for long-term conservation. However, the development of phylogenetically informed seed collecting programmes is difficult due to the insofar limited accessibility of biodiversity data represented in conservation facilities and to the lack of tailored methodological frameworks. Here, we used a comprehensive dataset spanning over 30 years conservation effort of 109 institutions across 29 European countries and provided a new flexible method to identify those species whose conservation would maximize the phylogenetic history representativeness should they become protected in conventional seed banks. Over one third (8,383 species) of the European angiosperm flora is currently secured in conventional seed banks, representing 60% of the total PD. However, this value is lower than the potential PD that could have been conserved because whole plant lineages are absent from banked seed lots. We show how securing further 4000 unsecured species selected from those lineages, would lead to protect 90% of total PD, as opposed to the 74% achieved from the same number of randomly selected unsecured species. Our method allows to prioritise among unsecured species using a stepwise-PD-maximisation procedure, adaptable to different resource availability scenarios. Nevertheless, for some of those species there are obstacles that prevent their seed collection and conservation. Thus, this study provides baseline data to promote better-grounded seed-based conservation policies and more generally, our new method will serve to prioritize among unsecured species of any taxonomic group so that the trade-off between secured evolutionary history and budget availability is maximised.