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

Abstract

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.

Short Communication: Sequence variation of DREB2 gene as a potential molecular marker for identifying resistant plants toward drought stress

“…Such variations, in turn, will also underlie genetic diversity between organisms. Many studies also indicate the presence of sequence variation in drought-responsive genes in a plant (Pomponio et al 2013;Yu et al 2013;Xia et al 2017). In this study, however, we focused on analyzing the sequence variations of DREB2 transcription factor (TF) genes in plants related to their function as a master regulator to manage and organize the expression of downstream drought-responsive genes located in the ABAindependent signaling pathway.…”

Anatomía comparada de la madera de Cupressaceae y su correspondencia con los estudios de filogenia

“…Muchos autores han estudiado la diversidad y variación genética que aparece en las masas naturales de Austrocedrus (Pastorino y Gallo 2001;Pastorino et al 2004;Arana et al 2010;Pomponio et al 2013), debido a su amplia distribución.…”