Identificación de subespecies de orquídeas pertenecientes al grupo de epidendrum nocturnum (orchidaceae), mediante la técnica molecular dna barcode

Abstract

The Epidendrum nocturnum group is a nomenclatural type of the genus Epidendrum. This specie is distributed throughout tropical America: Florida, Mexico, Colombia, Brazil, Venezuela, Peru, Ecuador and the Caribbean. It is estimated that there are approximately 35 species within this group. Epidendrum is the second largest genus in Ecuador, hence being so large generates a problem of classification of the species that compose it. DNA BARCODE is a molecular technique that facilitates the identification of species at the molecular level from sequenced DNA samples; however, it is not certain that the use of the chloroplastic genetic regions matK, ycf1 and rpoC1 can be used to make a specific differentiation at the subspecies level. Thus, plant samples were obtained from different areas of the country: Santo Domingo de los Tsáchilas, Imbabura, Pichincha, Napo and Pastaza to identify them by means of the aforementioned molecular technique. DNA was extracted by the Doyle and Doyle method, and a PCR was performed with these molecular markers to sequence the samples. The sequences obtained were then cleaned and those with a quality higher than 40% were used for the analyses; phylogenetic trees were prepared with the MEGA v 11.0 program, as well as a georeferencing map with the Google Earth platform. Finally, it was possible to conclude that the use of these molecular markers help to differentiate the subspecies of E. nocturnum, and observe a speciation phenomenon linked to the distribution of the different samples obtained due to changes at the genetic level.