Autoria: AZEVEDO, V. C. R.; KANASHIRO, M.; CIAMPI, A. Y.; GRATTAPAGLIA, D.

Resumo: In this work, we report on the population genetic structure of the endangered tree species Manilkara huberi, an Amazonian tree species intensely exploited due to the high density and resistance of its wood. We investigated the patterns of spatial distribution, genetic structure, and mating system using 7 microsatellite loci and here discuss the consequences for conservation and management of the species. To examine the population genetic structure, 481 adult trees and 810 seedlings were sampled from an area of 200 ha from a natural population in FLONA Tapajo´s, PA, Brazil. We found relatively high and consistent inbreeding levels (intrapopulation ?xation index [f] 0.175 and 0.240) and a signi?cant spatial genetic structure up to a radius of approximately 300 m, most likely due to a limited seed and pollen ?ow. The multilocus (tm) population outcrossing ratewas high (0.995), suggesting that the species is predominantly allogamouswith a pollen ?owrestricted to 47m. These results suggest thatM. huberi is spatially structured, consistentwith amodel of isolation by distance. Fragmentationmay therefore cause the loss of subpopulations, suggesting that management programs for production and conservation should include large areas. The genetic data also revealed that for ex situ conservation, seeds should be collected from more than 175 maternal trees, in order to keep an effective population size of 500. Furthermore, as the species is widely distributed across the Amazon Forest, samples should include several populations in order to represent the highest genetic diversity possible. These results provide a blueprint to guide the production and conservation management policies of this valuable timber species.

Ano de publicação: 2007

Tipo de publicação: Artigo de periódico

Unidade: Embrapa Recursos Genéticos e Biotecnologia

Palavras-chave: Amazonia, Brasil, Conservação, Fruta Tropical, Genética Vegetal, Manilkara Huberi, Maçaranduba, Árvore