Autor(es)

Nunes, Carlos E. P. ; Gerlach, Guenter ; Bandeira, Karen D. O. ; Gobbo-Neto, Leonardo ; Pansarin, Emerson R. ; Sazima, Marlies

• Tipo de documento: Artigo Científico
• Fonte: FLORA; v. 232, p. 10-pg., 2017-07-01.

Resumo

Floral volatile organic compounds (VOCs) are important signals in plant-pollinator communication and thus subjected to olfactory-mediated selection. Occasionally, phylogenetically unrelated plant species will converge towards similar patterns of floral scent signalling to harness pollinators, representing a common adaptive pollination niche. Catasetum cernuum and Gongora bufonia, epiphytic orchids that are native to the Atlantic Forest of southeastern South America, are exclusively pollinated by male Eufriesea violacea orchid-bees; we hypothesised that the two species have converged towards similar floral scent compositions to effectively attract these particular fragrance-seeking floral visitors. The similarity of the chemical composition of floral scent samples obtained through headspace collection was tested using multiple approaches of multivariate analyses (Multiple Response Permutation Procedure-MRPP). According to MRPP, floral scents of C. cernuum and G. bufonia are significantly different. Additionally, the floral scents of C. cernuum and G. bufonia present (E)-beta-ocimene and (E)-epoxyocimene as their major compounds, respectively. (E)-beta-ocimene is a common constituent of floral scents from euglossine-pollinated orchids, while (E)-epoxyocimene is quite rare in orchids' floral scents and it is found in only a few other species which occur outside the distribution range of C. cernuum, G. bufonia and E. violacea. However, 12 out of the 34 identified VOCs, including (E)-beta-ocimeneand (E)-epoxyocimene, are shared between both species. Therefore, we assume that both (E)-beta -ocimeneand (E)-epoxyocimene, either alone or mixed with other floral VOCs, play a major role in the specific association between these two orchids and their exclusive euglossine pollinator. (C) 2016 Elsevier GmbH. All rights reserved. (AU)

• Processo FAPESP: 14/20436-0 - Metabolômica como ferramenta na análise quimiotaxonômica do gênero C atasetum (ORC HIDAC EAE)
• Beneficiário: Karen Dayane de Oliveira Bandeira
• Modalidade de apoio: Bolsas no Brasil - Mestrado
• Processo FAPESP: 14/14969-6 - Evolução das características florais em um gênero neotropical exclusivamente polinizado por abelhas euglossine
• Beneficiário: Emerson Ricardo Pansarin
• Modalidade de apoio: Auxílio à Pesquisa - Regular