Hybridization and geographic distribution shapes the spatial genetic structure of two co-occurring orchid species

Autor(es)

Sujii, Patricia Sanae ^[1] ; Cozzolino, Salvatore ^[2] ; Pinheiro, Fabio ^[3]

Afiliação do(s) autor(es)

^[1] UDF Ctr Univ, Brasilia, DF - Brazil

^[2] Univ Napoli Federico II, Dept Biol, Complesso Univ Monte S Angelo, I-80126 Naples - Italy

^[3] Univ Estadual Campinas, Inst Biol, Dept Biol Vegetal, Campinas, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: HEREDITY; v. 123, n. 4, p. 458-469, OCT 2019.
• Citações Web of Science: 0

Resumo

Multiple ecological and life-history traits shape the fine-scale spatial genetic structure (FSGS) of a given population. The occurrence in core versus peripheral populations, levels of outcrossing, pollen and seed dispersal, and hybridization are important biological properties that influence the kinship of individuals within populations. We examined spatial genetic structure within 15 populations of Epidendrum fulgens and E. puniceoluteum distributed along a linear gradient of Brazilian coastal vegetation, including both allopatric and sympatric populations where the two orchid species hybridize. We analyzed 581 mapped specimens using nine simple sequence repeat loci, aiming to investigate how geographic distribution and hybridization shape within-population FSGS. A significant increase in FSGS was found towards peripheral populations, compared to core populations. Analysis of short-distance and long-distance components of FSGS identified biparental inbreeding and higher levels of FSGS at peripheral populations, when compared to core populations. In contrast, the relatively high density of reproductive adults in core populations potentially leads to highly overlapping seed and pollen movement, decreasing FSGS. Hybridization was an important factor shaping within-population spatial genetic structure at sympatric sites, decreasing the FSGS observed in parental species. Our results indicate that different ecological forces act in concert to create a gradient of FSGS along species distribution ranges, shaped by extensive levels of intraspecific and interspecific gene exchange. (AU)

• Processo FAPESP: 19/04918-9 - Evolution 2019
• Beneficiário: Fábio Pinheiro
• Modalidade de apoio: Auxílio à Pesquisa - Reunião - Exterior
• Processo FAPESP: 09/15052-0 - Filogeografia das espécies de Epidendrum (Orchidaceae) integrantes do clado Atlântico (subgênero Amphiglottium)
• Beneficiário: Fábio Pinheiro
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado
• Processo FAPESP: 06/54189-3 - Implicações taxonômicas da estrutura genética de populações naturais de E. cinnabarinum Salzm., E. denticulatum Barb. Rodr. e E. fulgens Brongn.
• Beneficiário: Fábio de Barros
• Modalidade de apoio: Auxílio à Pesquisa - Regular