Genetic diversity and population structure of endangered rosewood from the Peruvian Amazon using ISSR markers

ABSTRACT Rosewood, Aniba rosaeodora is an endangered species in Amazon forests and its natural stands have been heavily depleted due to over-exploitation for the cosmetic industry. This study aimed to investigate the genetic diversity and population structure of 90 rosewood accessions from eight localities in the Peruvian Amazon through 11 Inter Simple Sequence Repeats (ISSR) primers. The ISSR primers produced a sum of 378 bands, of which 375 (99.2%) were polymorphic, with an average polymorphism information content (PIC) value of 0.774. The mean effective number of alleles (Ne), Shannon informative index (I), gene diversity (He) and total gene diversity (Ht) were 1.485, 0.294, 0.453 and 0.252, respectively. Analysis of molecular variance (AMOVA) showed the presence of maximum variability within populations (88%). The Structure algorithm, neighbor joining and principal coordinate analysis (PCoA) grouped the 90 rosewood accessions into three main populations (A, B and C). Diversity indices at the inter-population level revealed a greater genetic diversity in population A, due to higher gene flow. The neighbor-joining analysis grouped populations A and B, while population C was found to be divergent at the inter population level. We concluded that population A reflects higher genetic diversity and should be prioritized for future management and conservation plans. RESUMEN Palo de rosa, Aniba rosaeodora es una especie en peligro de extinción en los bosques amazónicos. Sus rodales naturales se han agotado debido a la sobreexplotación para la industria cosmética. Este estudio tuvo como objetivo investigar la diversidad genética y estructura poblacional de 90 accesiones de palo de rosa de ocho localidades en la Amazonía Peruana utilizando 11 marcadores de Inter Secuencias Simples Repetidas (ISSR). Los marcadores ISSR produjeron una suma de 378 bandas, de las cuales 375 (99,2%) fueron polimórficas, con un valor promedio de contenido de información de polimorfismo (PIC) de 0,774. El promedio del número efectivo de alelos (Ne), índice informativo de Shannon (I), diversidad genética (He) y diversidad genética total (Ht) fueron 1,485; 0,294; 0,453 y 0,252; respectivamente. El análisis de varianza molecular (AMOVA) mostró la presencia de máxima variabilidad dentro de las poblaciones (88%). El algoritmo Structure, neighbor joining y análisis de coordenadas principales (PCoA) agruparon las 90 accesiones de palo de rosa en tres poblaciones principales (A, B y C). Los índ