Abstract
Mediterranean forests are fragile ecosystems vulnerable to recent global warming and reduction of precipitation, and a long-term negative effect is expected on vegetation with increasing drought and in areas burnt by fires. We investigated the spatial distribution of genetic variation of Arbutus unedo in the western Iberia Peninsula, using plastid markers with conservation and provenance regions design purposes. This species is currently undergoing an intense domestication process in the region, and, like other species, is increasingly under the threat from climate change, habitat fragmentation and wildfires. We sampled 451 trees from 15 natural populations from different ecological conditions spanning the whole species’ distribution range in the region. We applied Bayesian analysis and identified four clusters (north, centre, south, and a single-population cluster). Hierarchical AMOVA showed higher differentiation among clusters than among populations within clusters. The relatively low within-clusters differentiation can be explained by a common postglacial history of nearby populations. The genetic structure found, supported by the few available palaeobotanical records, cannot exclude the hypothesis of two independent A. unedo refugia in western Iberia Peninsula during the Last Glacial Maximum. Based on the results we recommend a conservation strategy by selecting populations for conservation based on their allelic richness and diversity and careful seed transfer consistent with current species’ genetic structure.
Highlights
The contemporary genetic structure of a species offers important information about its responses to past geological and climatic events, which had often played a crucial role in shaping the current distribution range
Statistical significance may indicate the presence of a Genetic structure in strawberry tree phylogeographic structure [46], i.e., closely related haplotypes are more often found in the same population than would be expected by chance
We found no correlation between D2sh and genetic diversity estimates (Table 3)
Summary
The contemporary genetic structure of a species offers important information about its responses to past geological and climatic events, which had often played a crucial role in shaping the current distribution range. Arbutus unedo fruit has strong antioxidant properties and it can be consumed fresh or processed, and it is used in Portugal to produce the liquor ‘aguardente’, an important source of income for land users, which has led to an on-going process of domestication of the species through clonal propagation of genotypes selected for fruit quality [15] and to the use of seeds from unknown origin This species has economic importance to be used in Portugal and southern Europe, with different commercial uses from processed and fresh fruit production to ornamental, pharmaceutical and chemical industrial applications, due to the phenolic acids and terpenoid compounds with strong antioxidant activity, vitamin C and tannin content [15 and references therein, 16, 17]. Our specific aims were to: i) investigate the spatial distribution of genetic variation of A. unedo in Portugal, and to ii) provide recommendations for species’ conservation and help in provenance region design
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
