DNA sequence variation of drought-response candidate genes in Austrocedrus chilensis

Background: Austrocedrus chilensis (D. Don) Pic. Ser. et Bizzarri commonly known as Patagonian cypress is a member of the Cupressaceae family, characterized by a high adaptive potential for growing in marginal areas and good timber quality. The species grows over a wide area and under a wide range of rainfall. This study assessed adaptive genetic variation at SNP level in candidate genes involved in response to drought stress. Results: A total of 18 single nucleotide polymorphisms (SNPs) were found among 1,428 bp. Average nucleotide diversity value (π = 0.00312) was similar to those previously reported in other Cupressaceae. The Fst average among genes and populations was 0.163 and the lowest differentiation was observed in continuous and humid populations. A number of neutrality tests were applied to find evidence of positive selection in our candidate gene set, but only AcAQP2 gene in Pedregoso and San Ramón populations revealed significant departures from neutrality with positive values suggesting balancing selection. Conclusions: In this study we report the levels of nucleotide diversity searched in some drought stress candidate genes in Austrocedrus chilensis and the selective factors that may be acting on this species.Fil: Pomponio, Maria Florencia. Instituto Nacional de Tecnologia Agropecuaria. Centro Nacional de Inv. Agropecuarias. Centro de Invest.de Recursos Naturales. Instituto de Recursos Biologicos; ArgentinaFil: Torales, Susana. Instituto Nacional de Tecnologia Agropecuaria. Centro Nacional de Inv. Agropecuarias. Centro de Invest.de Recursos Naturales. Instituto de Recursos Biologicos; ArgentinaFil: Gallo, Leonardo. Instituto Nacional de Tecnologia Agropecuaria. Centro Reg.patagonia Norte. Estacion Exptal.agrop.s.c.de Bariloche. Grupo de Genetica Forestal; ArgentinaFil: Pastorino, Mario Juan. Instituto Nacional de Tecnologia Agropecuaria. Centro Reg.patagonia Norte. Estacion Exptal.agrop.s.c.de Bariloche. Grupo de Genetica Forestal; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Marchelli, Paula. Instituto Nacional de Tecnologia Agropecuaria. Centro Reg.patagonia Norte. Estacion Exptal.agrop.s.c.de Bariloche. Grupo de Genetica Forestal; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Cervera, María Teresa. Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria. Centro de Investigación Forestal; EspañaFil: Marcucci Poltri, Susana Noemí. Instituto Nacional de Tecnologia Agropecuaria. Centro Nacional de Inv. Agropecuarias. Centro de Invest.de Cs.veterinarias y Agronomicas. Instituto de Biotecnologia; Argentin