Genetic diversity and population structure of Jubaea chilensis (Molina)
Baill., an endemic and monotype gender from Chile, based on SNPs markers
Abstract
Jubaea chilensis (Molina)Baill., also named Chilean palm, is an endemic
species found in the coastal area of Mediterranean sclerophyllous forest
in Chile. It has a highly restricted and fragmented distribution along
the coast, being under intense exploitation and anthropogenic impact.
Based on 1,038 SNP markers, we evaluated the genetic diversity and
population structure among six J. chilensis natural groups. We observed
low levels of genetic diversity (overall HE = 0.024 and HO =0.014), a
deficit of heterozygotes, and high levels of inbreeding (mean FIS =
0.424), with little or no random mating. All Wright fixation index and
Nei’s genetic distance pairwise comparisons indicated moderate
differentiation among populations, with a tendency to similarity. There
was no evidence of isolation by distance (r =-0.214, P =0.799). In the
cluster analysis, we observed a closer relationship among Culimo,
Cocalán and Candelaria populations. The K value that best represented
the spatial distribution of genetic diversity was ∆K =3. Habitat
fragmentation and deterioration of the sclerophyllous forest may have
driven inbreeding and low levels of genetic diversity in the palm groves
of J. chilensis, putting the persistence of present and future
populations at risk. In this scenario, it is imperative to reclassify J.
chilensis as an endangered species, as well as a Natural Monument, in
order to improve conservation efforts, the species management, and the
environmental protection Also, the preservation of genetically different
individuals may increase the overall genetic variability required to
sustain the species persistence in the context of climate change and
anthropogenic disturbance.