Estimation of genetic diversity in seedlings of Plantago algarbiensis, an endangered species endemic to the south of Portugal in risk of global extinction

Abstract

Plantago algarbiensis samp is an endangered species endemic to the Algarve, in southern Portugal. In the present work, the genetic diversity of three populations was assessed by RAPD markers. Samples were amplified using ten primers that generated 145 markers, 80% of which were polymorphic. Tunes population presented the highest polymorphism percentage (73.68%) and Algoz the lowest (67.67%). In the cluster analysis, two major groups were formed, one including individuals from Gambelas and the other clustered together individuals from the other populations. The highest level of genetic diversity, estimated by both Nei’s gene diversity and Shannon’s information measure, was found in Tunes and the lowest in Algoz. From the estimates of Shannon’s index, the proportion of the diversity within populations was 86.12% and that among populations was 13.88%. Similar results were obtained by AMOVA analysis. A correlation was found between geographic distance and genetic differentiation among populations. The Nm values obtained suggest a high level of gene flow among populations, which was inversely proportional to the distance between populations. RAPDs proved to be a useful tool to determine the genetic diversity of P. algarbiensis populations. The data obtained can be used to develop effective conservation strategies to prevent the decline of populations.