Association of loganin contents with the genetic characterization of natural populations of Palicourea rigida Kunth determined by AFLP molecular markers

Extracts of the medicinal plant Palicourea rigida Kunth, popularly known as douradinha, are widely used for treating urinary tract disorders. Unfortunately, nowadays this is one of the species endemic to Brazilian Cerrado that is at greatest risk of extinction. The aim of the this work was to use AFLP molecular markers to determine the genetic structure and diversity of eight natural populations of P. rigida and to associate their genetic characteristics with loganin production in order to obtain provide relevant information to promote programs for the conservation of this valuable medicinal plant. A total of 120 polymorphic bands were scored and higher proportion of genetic diversity was found in inter-populations (64%) rather than in intra-populations (36%). Fst value was found to be significantly greater than zero (0.3601), demonstrating the complex genetic structure of P. rigida populations. Accessions collected from Cristalina, GO, showed higher percentage of polymorphic loci (65.5%) and the highest genetic diversity. Analysis of Molecular variance (AMOVA) demonstrated 63.9% of intra-population genetic variation. The lowest genetic variability was detected among accessions from the population found in Sacramento, MG. No spatial standard was observed for P. rigida population, suggesting a partially isolated island model. It was observed a minor but significant positive correlation (r = 0.22) between chemical and genetic matrices. The association between chemical and genetic data indicated that environmental factors promoted the loganin production in populations growing in Luziânia, GO, and therefore accessions from those populations should be considered as prime material for initiating the conservation process of P. rigida. •Palicourea rigida HBK extracts are widely used for treating urinary tract disorders.•AFLP technique was efficient to determine P. rigida genetic diversity.•Higher proportion of genetic variation was found inter-populations (64%).•Environmental factors enhance loganin production in P. rigida.