RESUMO
Panax vietnamensis Ha et Grushv. is a precious medicinal species native to the tropical forests of Vietnam. Due to habitat loss and over-harvesting, this species is endangered in Vietnam. To conserve the species, we investigated genetic variability and population structure using nine microsatellites for 148 individuals from seven populations across the current distribution range of P. vietnamensis in Vietnam. We determined a moderate genetic diversity within populations (HO = 0.367, HE = 0.437) and relatively low population differentiation (the Weir and Cockerham index of 0.172 and the Hedrick index of 0.254) and showed significant differentiation (P < 0.05), which suggested fragmented habitats, over-utilization and over-harvesting of P. vietnamensis. Different clustering methods revealed that individuals were grouped into two major clusters, which were associated with gene flow across the geographical range of P. vietnamensis. This study also detected that ginseng populations can have undergone a recent bottleneck. We recommend measures in future P. vietnamensis conservation and breeding programs.
Panax vietnamensis Ha et Grushv. é uma espécie medicinal preciosa nativa das florestas tropicais do Vietnã. Por causa da perda de hábitat e da colheita excessiva, essa espécie está ameaçada de extinção no Vietnã. Para conservá-la, investigamos a variabilidade genética e a estrutura populacional usando nove microssatélites para 148 indivíduos de sete populações em toda a distribuição atual de P. vietnamensis no Vietnã. Determinamos uma diversidade genética moderada dentro das populações (HO = 0,367 e HE = 0,437) e diferenciação populacional relativamente baixa (índice de Weir e Cockerham de 0,172 e índice de Hedrick de 0,254), com diferenciação significativa (P < 0,05), o que sugeriu fragmentação de hábitats, sobreutilização e sobre-exploração de P. vietnamensis. Diferentes métodos de agrupamento revelaram que os indivíduos foram agrupados em dois agrupamentos principais, que foram associados ao fluxo gênico em toda a área geográfica de P. vietnamensis. Este estudo também detectou que as populações de ginseng podem ter sofrido um gargalo recente. Recomendamos medidas em futuros programas de conservação e melhoramento de P. vietnamensis.
Assuntos
Plantas Geneticamente Modificadas , Panax , VietnãRESUMO
Panax vietnamensis Ha et Grushv. is a precious medicinal species native to the tropical forests of Vietnam. Due to habitat loss and over-harvesting, this species is endangered in Vietnam. To conserve the species, we investigated genetic variability and population structure using nine microsatellites for 148 individuals from seven populations across the current distribution range of P. vietnamensis in Vietnam. We determined a moderate genetic diversity within populations (HO = 0.367, HE = 0.437) and relatively low population differentiation (the Weir and Cockerham index of 0.172 and the Hedrick index of 0.254) and showed significant differentiation (P < 0.05), which suggested fragmented habitats, over-utilization and over-harvesting of P. vietnamensis. Different clustering methods revealed that individuals were grouped into two major clusters, which were associated with gene flow across the geographical range of P. vietnamensis. This study also detected that ginseng populations can have undergone a recent bottleneck. We recommend measures in future P. vietnamensis conservation and breeding programs.