The restoration of the endangeredSambucus palmensisafter 30 years of conservation actions in the Garajonay National Park: genetic assessment and niche modeling

Abstract

The translocation of individuals or the reinforcement of populations are measures in the genetic rescue of endangered species. Although it can be controversial to decide which and how many individuals must be reintroduced, populations can benefit from reinforcements. Sambucus palmensis is a critically endangered endemic to the Canary Islands. During the past 30 years, the Garajonay National Park (La Gomera) has carried out an intensive program of translocations using cuttings, due to the low germination rates of seeds. To assess the effect of the restorations on the population genetics of S. palmensis in La Gomera, we collected 402 samples from all the restored sites and all known natural individuals, which were genotyped with seven microsatellite markers. In addition, we conducted a species distribution modeling approach to assess how restorations fit the ecological niche of the species. Results show that there is a high proportion of clone specimens due to the propagation method, and the natural clonal reproduction of the species. Nonetheless, the observed heterozygosity has increased with the restorations and there still are private alleles and unique genotypes in the natural populations that have not been considered in the restorations. The population of Liria constitutes a very important genetic reservoir for the species. To optimize future reintroductions, we have proposed a list of specimens that are suitable for the extraction of seeds or cuttings in a greenhouse, as well as new suitable areas obtained by the species distribution models.

Wild Sambucus nigra L. from north-east edge of the species range: A valuable germplasm with inhibitory capacity against SARS-CoV2 S-protein RBD and hACE2 binding in vitro

“…These data conform well with the generally observed low proportion of among-population genetic variability in outcrossing woody perennials dispersed through ingestion ( Hamrick and Godt, 1996 ). Although data on genetic variability of wild S. nigra populations is scarce, studies in related species – S. palmensis Link and S. canadensis L. observed a similar trend of high within-site genetic variation compared with genetic variability between different sampling sites and sampling regions ( Rodríguez-Rodríguez et al, 2018 ; Johnson et al, 2008 ; Sosa et al, 2010 ).…”

Guidelines for genetic monitoring of translocated plant populations

“…2015; Rodríguez‐Rodríguez et al. 2018). Natural functioning populations may serve as reference populations (Menges 2008).…”

“…Genetic data should be obtained for the populations used as source for translocation, and for several generations of the translocated populations (transplants and newly established individuals and their seed progeny). For some species, the long recruitment time lags represent a constraint for monitoring new generations (Bowles et al 2015;Fotinos et al 2015;Rodríguez-Rodríguez et al 2018). Natural healthy populations may serve as reference populations (Menges 2008).…”

“…2015; Rodríguez‐Rodríguez et al. 2018). Practical information and a framework for implementing genetic surveys of threatened animal and plant species are available (e.g., Schwartz et al.…”

“…To describe genetic divergence among generations and among translocated/natural populations, genetic distance and differentiation statistics (e.g. F ST , G ST , Jost's D) are usually combined with Bayesian clustering analyses and/or multivariate analyses (Appendix S1;Jombart et al 2010; Alonso et al 2014;Fotinos et al 2015;Rodríguez-Rodríguez et al 2018; …”