Research Article Variability of <i>Myrciaria</i> <i>dubia</i> genotypes (Myrtaceae) in native populations of Roraima state

Abstract

Camu-camu, Myrciaria dubia (Myrtaceae) is a native species of the Amazon Rainforest that has been attracting attention worldwide and arousing great interest in the food and pharmacological industries due to the high concentrations of ascorbic acid in its fruit, which is exported to several countries. Characterizing different materials of M. dubia by means of molecular markers allows integration of agronomic and molecular information to aid in the search for more promising varieties. We examined the genetic variability of 11 populations of this species distributed along the Branco River hydrographic basin in state of Roraima in northern Brazil. The populations were defined taking into account the origin of the subsample. The 55 sub-samples present in the Embrapa Roraima Germplasm Collection were evaluated using five ISSR initiators (UBC 811, UBC 812, UBC 817, UBC 868 and UBC 880). The five primers tested generated 64 fragments, with a 98% polymorphism rate. The greatest genetic variation was expressed within the populations (66.6%), while the lowest divergence was determined among the populations (33.4%) of the collection. There was a significant correlation between genetic and geographical distances ©FUNPEC-RP www.funpecrp.com.br Genetics and Molecular Research 19 (2): gmr18418 C.G. Souza et al. 2 (Mantel test, r = 0.3%, P < 0.01). Analysis with the UPGMA method gave four subgroups showing that various individuals are genetically divergent and can be used in genetic breeding programs.

Potential Vulnerability of Natural Populations of Camu-camu (Myrciaria dubia) to Anthropogenic Stressors in Southwestern Amazon

“…Germplasm collections with specimens from all the Amazon basin are active in Brazil at INPA (Instituto Nacional de Pesquisa da Amazônia) and EMBRAPA, with ex-situ collections in Manaus, Belem and Boa Vista (Nascimento et al, 2013;Sakazaki et al, 2022;Yuyama & Valente, 2011), and in Peru at IIAP (Instituto de Investigaciones de la Amazonía Peruana) from western Amazonia (Pinedo-Panduro et al, 2020;Šmíd et al, 2017). Genetic studies have shown a high intra-and inter-population variability with a high geographic structure (Nunes et al, 2017, Rojas et al, 2011Šmíd et al, 2017;Souza et al, 2020), which indicates that to conserve the existing genetic diversity it will be needed to sample at large geographic scales.…”