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)

Efeito de diferentes reguladores de crescimento na regeneração in vitro de pau-rosa (Aniba rosaeodora Ducke) / Effect of differents growth regulators in vitro propagation of Aniba rosaeodora Ducke

O objetivo deste trabalho foi estabelecer um protocolo para a regeneração in vitro de pau-rosa (Aniba rosaeodora Ducke), utilizando brotações apicais e segmentos nodais inoculados em meio de cultura com distintas concentrações de diferentes reguladores de crescimento. Explantes esterilizados com soluções de benomyl (4,0 g.L-1) por 24 horas e hipoclorito de sódio a 20% + tween 20 por 20 minutos, foram submetidos a um experimento de indução de broto, raiz e calo em meio MS1 acrescido de 30g.L-1 de sacarose e 9g.L-1 de agar, suplementado com BAP (0,0 e 4,0 mg.L-1), ANA, AIA e 2,4-D (0,0; 3,0 e 6,0 mg.L-1), e suas respectivas combinações. O delineamento utilizado foi o inteiramente casualizado em esquema fatorial 7 X 2, com 14 tratamentos e 15 repetições cada, onde foram analisados o número médio de brotos, raízes e calo. Após 90 dias, os resultados mostraram que a presença de auxinas é fundamental para a formação dos parâmetros induzidos nos explantes de pau-rosa. O meio de cultura contendo 4,0 mg.L-1 de BAP + 6,0 mg.L-1 de AIA apresentou a melhor média para a brotação com 2,13 brotos/explante. Para o enraizamento o meio contendo 3,0 mg.L-1 de ANA foi o mais eficiente, apresentando uma média de 2,53 raízes/explante. Em relação à indução de calo, todos os tratamentos apresentaram calogênese, porém o meio suplementado com 4,0 mg.L-1 de BAP + 6,0 mg.L-1 de 2,4-D, apresentou a melhor média, 1,67 calos/explante.

The objective of this work was to establish a protocol for in vitro regeneration of rosewood (Aniba rosaeodora Ducke), using apical and nodal segments inoculated in culture medium with various concentrations of growth regulators. Explants disinfected with solutions of benomyl (4,0 g.L-1) for 24 hours and sodium hipoclorite in 20% + tween 20 for 20 minutes were submitted in an experiment of shoot, root and callus induction in MS medium, with 30 g.L-1 of sucrose and 9,0 g.L-1 of agar added with the growth regulators: BAP (0,0 and 4,0 mg.L-1), ANA, AIA and 2,4-D (0,0; 3,0 and 6,0 mg.L-1), and their respective combinations. The design was complete randomized in arranged factorial 7 X 2, with 14 treatments and 15 replications, where about the explants were analysed the number of shoot, root and callus . After 90 days, the results showed that the presence of auxins is fundamental to induce buds, roots and callus . The medium was contained 4,0 mg.L-1 BAP + 6,0 mg.L-1 AIA showed the best average for shooting with 2,13 buds/explants. In the rooting, the medium was contained 3,0 mg.L-1 of ANA was the more efficient, showed 2,53 roots/explant. However, all the treatments obtained formation of callus, but the medium with 4,0 mg.L-1 BAP + 6,0 mg.L-1 2,4-D showed the best result,1.67 callus/explant.