Isolation and characterization of microsatellite markers for Bertholletia excelsa (Lecythidaceae) population genetic analysis

Abstract

ABSTRACT. Seven polymorphic microsatellite markers were developed and validated for Bertholletia excelsa (Brazil nut tree) population genetic studies. This species is a widespread monotypic Amazonian tree with high non-timber economic value. Unfortunately, Brazil nut production is currently less than 25% of historical production levels, because of extensive deforestation. All pairs of primers produced clearly interpretable and polymorphic bands. No linkage disequilibrium was observed in an analysis of 46 individuals from one population, three to seven alleles per locus were observed; the expected heterozygosity ranged from 0.378 to 0.978, with significant heterozygote excess for four loci. An analysis of individuals from two populations showed private alleles at all loci. These primer pairs will be useful for population studies, especially for comparing samples from different parts of the Amazon forest.

Research Article Genetic diversity of Brazil-nut populations naturally occurring in the municipality of Alta Floresta, MT, Brazil

“…The He and Ho values corroborate the results of Reis et al (2009) for B. excelsa, in which the authors reported lower observed than expected heterozygosity in eight SSR loci (Bex02, Bex03, Bex12, Bex27, Bex30, Bex32, Bex33, and Bex37), with SSR locus Bex06 displaying the highest expected heterozygosity (0.950), as occurred in in this study. Contrasting results were found by Sujii et al (2013) and Sujii et al (2015), who used other microsatellite markers developed for B. excelsa and obtained He values lower than Ho values. According to Alves et al (2007), most tropical tree species have shown a higher number of alleles per locus and consequently greater expected heterozygosity.…”

“…The total number of alleles (70) and the average number of alleles per locus (6.36) found in this study were lower than those found by Reis et al (2009), who optimized the same SSR loci for B. excelsa and obtained an average of 9.9 alleles per locus. However, Sujii et al (2013) isolated and characterized seven microsatellite primers for B. excelsa and found a lower number of alleles per locus (average of five). Overall, the average number of alleles per locus found for B. excelsa agrees with the results found of other tree species using microsatellite markers.…”

Genetic structure of Bertholletia excelsa populations from the Amazon at different spatial scales

“…Individuals were genotyped with eleven microsatellite markers, seven of which were developed by Sujii et al (2013), and four developed by Reis et al (2009). Both the conditions of amplification reactions and the characterization of loci are as described previously (Sujii et al 2013).…”

“…Both the conditions of amplification reactions and the characterization of loci are as described previously (Sujii et al 2013).…”

Research Article Hierarchical outcrossing among and within fruits in Bertholletia excelsa Bonpl. (Lecythidaceae) open-pollinated seeds

“…Moreover, they amplify large numbers of alleles (Hoshino et al, 2002) and represent low cost in investigations about the genetic diversity and mating system of tree species when the primers were already developed, such as in B. excelsa. Reis et al (2009) developed 12 polymorphic microsatellite markers to the species and Sujii et al (2013) developed another 12. In addition, genetic studies with molecular markers in fragmented forests using natural seeds or regenerates helped evidencing processes such as genetic drift, gene flow, selection and mating system (Carvalho et al, 2010;Wadt et al, 2015;Baldoni et al, 2017).…”