Applicability of inter-primer binding site iPBS- retrotransposon marker system for the assessment of genetic diversity and population structure of Peruvian rosewood (Aniba rosaeodora Ducke) germplasm.

BACKGROUND: Rosewood (Aniba rosaeodora Ducke), which has a great demand due to its essential oil globally, is an evergreen tree of the Amazon forests. Rosewood natural stands have been depleted through deforestation and the destruction of habitat. Currently, rosewood is included in the ICUN red list of endangered species. METHODS AND RESULTS: The 11 highly polymorphic primers amplified total 305 bands of which 301 (98.69%) were polymorphic. The number of effective alleles (Ne), Shannon's information index (I), overall gene diversity (Ht), gene diversity (h), and polymorphism information content (PIC) were (1.562), (0.505), (0.330), (0.337) and (0.343), respectively. These diversity indices explored high genetic diversity in rosewood germplasm. Among studied germplasm, the Santa Marta population was found most diverse by reflecting higher values of diversity indices while the Zungarococha population was found least diverse. The analysis of molecular variance (AMOVA) revealed that 79% of the genetic variation was within the populations. The STRUCTURE algorithm, unweighted pair group with arithmetic mean (UPGMA), and principal coordinate's analysis (PCoA) separated all germplasms into different population groups according to their geographic locations. Santa Marta population was found more diverse by reflecting higher values of diversity indices. The maximum genetic distance (0.868) was found between the Huajoya-10 and Nanay-3. In this investigation, iPBS- retrotransposon marker system was used to explore the genetic diversity of Peruvian rosewood germplasm. CONCLUSIONS: The results in this study such as higher genetic diversity indices, AMOVA (79%) within population and PIC value (0.343) showed the utility and reproducibility of iPBS-retrotransposons in this species successfully. The STRUCTURE algorithm separated the germplasms into six population groups according to their geographic locations. These results have valuable information for the conservation, management strategies and future breeding activities of rosewood.

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

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. (AU)