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Fine-scale spatial genetic structure of Dalbergia nigra (Fabaceae), a threatened and endemic tree of the Brazilian Atlantic Forest.

de Oliveira Buzatti RS, Ribeiro RA, de Lemos Filho JP, Lovato MB - Genet. Mol. Biol. (2012)

Bottom Line: No strong evidence of bottleneck or effects of human-disturbance was found.This study highlights that long-term efforts to protect a large area of Atlantic Forest have been effective towards maintaining the genetic diversity of D. nigra.The results of this study are important towards providing a guide for seed collection for ex-situ conservation and reforestation programmes of this threatened species.

View Article: PubMed Central - PubMed

Affiliation: Departamento de Biologia Geral, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil.

ABSTRACT
The Atlantic Forest is one of the most diverse ecosystems in the world and considered a hotspot of biodiversity conservation. Dalbergia nigra (Fabaceae) is a tree endemic to the Brazilian Atlantic Forest, and has become threatened due to overexploitation of its valuable timber. In the present study, we analyzed the genetic diversity and fine-scale spatial genetic structure of D. nigra in an area of primary forest of a large reserve. All adult individuals (N = 112) were sampled in a 9.3 ha plot, and genotyped for microsatellite loci. Our results indicated high diversity with a mean of 8.6 alleles per locus, and expected heterozygosity equal to 0.74. The co-ancestry coefficients were significant for distances among trees up to 80 m. The Sp value was equal to 0.017 and indirect estimates of gene dispersal distances ranged from 89 to 144 m. No strong evidence of bottleneck or effects of human-disturbance was found. This study highlights that long-term efforts to protect a large area of Atlantic Forest have been effective towards maintaining the genetic diversity of D. nigra. The results of this study are important towards providing a guide for seed collection for ex-situ conservation and reforestation programmes of this threatened species.

No MeSH data available.


Related in: MedlinePlus

Map of part of southeastern Brazil showing remaining areas of Atlantic Forest, including the Rio Doce State Park (a); the Rio Doce State Park and the location of Campolina population (a) and the distribution (in meters) of the 112 adult individuals of Dalbergia nigra sampled within a 9.3 ha plot of the Campolina population (c).
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f1-gmb-35-838: Map of part of southeastern Brazil showing remaining areas of Atlantic Forest, including the Rio Doce State Park (a); the Rio Doce State Park and the location of Campolina population (a) and the distribution (in meters) of the 112 adult individuals of Dalbergia nigra sampled within a 9.3 ha plot of the Campolina population (c).

Mentions: Samples of D. nigra used for this study were collected in the Rio Doce State Park Biological Reserve (from 19°48′18″ to 19°29′24″ S and 42°38′30″ to 42°28′18″ W), which was implemented in 1944 (IEF, 2002) and is located in the state of Minas Gerais, southeastern Brazil (Figure 1a, b). It is the largest remnant of Atlantic Forest in this state, with a total area of 36,000 ha of native primary and secondary vegetation (Solá, 2001). The sampled area, named Campolina, comprises 130 ha of undisturbed primary forest vegetation (Ribeiro et al., 2005). One plot of 9.3 ha was randomly delimited and the cambium of 112 adult trees was sampled (density = 12.0 trees/ha) for the analysis of diversity and fine-scale spatial genetic structure. The diameter at breast height (dbh) of the sampled trees ranged from 10 to 53 cm, with an average of 23.3 cm and median of 21 cm. The spatial distribution of trees (Figure 1c) was recorded using GPS Garmin 60CSx and visualised with TrackMaker 11.7 software (Ferreira Jr, 2001).


Fine-scale spatial genetic structure of Dalbergia nigra (Fabaceae), a threatened and endemic tree of the Brazilian Atlantic Forest.

de Oliveira Buzatti RS, Ribeiro RA, de Lemos Filho JP, Lovato MB - Genet. Mol. Biol. (2012)

Map of part of southeastern Brazil showing remaining areas of Atlantic Forest, including the Rio Doce State Park (a); the Rio Doce State Park and the location of Campolina population (a) and the distribution (in meters) of the 112 adult individuals of Dalbergia nigra sampled within a 9.3 ha plot of the Campolina population (c).
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC3526093&req=5

f1-gmb-35-838: Map of part of southeastern Brazil showing remaining areas of Atlantic Forest, including the Rio Doce State Park (a); the Rio Doce State Park and the location of Campolina population (a) and the distribution (in meters) of the 112 adult individuals of Dalbergia nigra sampled within a 9.3 ha plot of the Campolina population (c).
Mentions: Samples of D. nigra used for this study were collected in the Rio Doce State Park Biological Reserve (from 19°48′18″ to 19°29′24″ S and 42°38′30″ to 42°28′18″ W), which was implemented in 1944 (IEF, 2002) and is located in the state of Minas Gerais, southeastern Brazil (Figure 1a, b). It is the largest remnant of Atlantic Forest in this state, with a total area of 36,000 ha of native primary and secondary vegetation (Solá, 2001). The sampled area, named Campolina, comprises 130 ha of undisturbed primary forest vegetation (Ribeiro et al., 2005). One plot of 9.3 ha was randomly delimited and the cambium of 112 adult trees was sampled (density = 12.0 trees/ha) for the analysis of diversity and fine-scale spatial genetic structure. The diameter at breast height (dbh) of the sampled trees ranged from 10 to 53 cm, with an average of 23.3 cm and median of 21 cm. The spatial distribution of trees (Figure 1c) was recorded using GPS Garmin 60CSx and visualised with TrackMaker 11.7 software (Ferreira Jr, 2001).

Bottom Line: No strong evidence of bottleneck or effects of human-disturbance was found.This study highlights that long-term efforts to protect a large area of Atlantic Forest have been effective towards maintaining the genetic diversity of D. nigra.The results of this study are important towards providing a guide for seed collection for ex-situ conservation and reforestation programmes of this threatened species.

View Article: PubMed Central - PubMed

Affiliation: Departamento de Biologia Geral, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil.

ABSTRACT
The Atlantic Forest is one of the most diverse ecosystems in the world and considered a hotspot of biodiversity conservation. Dalbergia nigra (Fabaceae) is a tree endemic to the Brazilian Atlantic Forest, and has become threatened due to overexploitation of its valuable timber. In the present study, we analyzed the genetic diversity and fine-scale spatial genetic structure of D. nigra in an area of primary forest of a large reserve. All adult individuals (N = 112) were sampled in a 9.3 ha plot, and genotyped for microsatellite loci. Our results indicated high diversity with a mean of 8.6 alleles per locus, and expected heterozygosity equal to 0.74. The co-ancestry coefficients were significant for distances among trees up to 80 m. The Sp value was equal to 0.017 and indirect estimates of gene dispersal distances ranged from 89 to 144 m. No strong evidence of bottleneck or effects of human-disturbance was found. This study highlights that long-term efforts to protect a large area of Atlantic Forest have been effective towards maintaining the genetic diversity of D. nigra. The results of this study are important towards providing a guide for seed collection for ex-situ conservation and reforestation programmes of this threatened species.

No MeSH data available.


Related in: MedlinePlus