Abstract

Background and aims: The extreme conditions in the Chilean Atacama Desert are a major hurdle for the survival of any organism. Despite this, several legume populations of Geoffroea decorticans have thrived within this harsh, hostile environment for centuries. Here, we sought to determine the genetic variability in G. decorticans populations, given its wide distribution across the Atacama Desert, the driest and most ancient desert on Earth. The specific aims of the present study were to determinate the level of genetic diversity and assess genetic structure in eight populations of G. decorticans from Chilean Atacama Desert. M&M: Eighty-four G. decorticans individuals were selected for sampling across eight localities in Northern Chile. Five microsatellites were used to analyze genetic diversity, differentiation among populations, population structure and gene flow. Results: The majority of the analyzed populations from the Atacama Desert displayed a high genetic diversity, with the exception of Pachica population. G. decorticans (chanar) populations also displayed a high genetic differentiation and a moderate gene flow given by the natural barrier imposed by the Atacama Desert. The eight chanar populations studied were separated in groups from Northern and Southern regions. Conclusions: Microsatellites have provided valuable baseline information to understand the genetic diversity and structure of G. decorticans populations at the Atacama Desert.