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(Referência obtida automaticamente do Web of Science, por meio da informação sobre o financiamento pela FAPESP e o número do processo correspondente, incluída na publicação pelos autores.)

A reduced, yet functional, nectary disk integrates a complex system of floral nectar secretion in the genus Zeyheria (Bignoniaceae)

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Autor(es):
Machado, Silvia Rodrigues ; de Souza, Camila Vaz ; Guimaraes, Elza
Número total de Autores: 3
Tipo de documento: Artigo Científico
Fonte: Acta Botanica Brasilica; v. 31, n. 3, p. 344-357, JUL-SEP 2017.
Citações Web of Science: 4
Resumo

The genus Zeyheria (Bignoniaceae) comprises only two species, both of which have been described as possessing a reduced and non-functional nectary disk. Despite the importance of this evolutionary change in the floral nectary, these functional assumptions have been based on disk size and on the distribution, abundance and histochemistry of corolla-borne trichomes. By combining methods on light and electron microscopy, here we investigated the functionality of the reduced nectary disk and describe all of the tissues and structures of the nectar chamber in order to determine the sites of floral nectar secretion in both Zeyheria species.. Our data find the floral nectary traits of both species to be very similar, although differing in their cellular contents. Subcellular evidence in both species indicated that disk, stipe and petal axils were, predominantly, involved in hydrophilic secretion, while capitate glandular trichomes produced lipophilic secretion and papillae produced mixed secretion. Our study shows that in spite of its reduced size, the reduced disk functions in nectar secretion in both species of Zeyheria. This kind of nectary system is a novelty for Bignoniaceae, since it comprises several tissues and structures functioning in an integrated fashion. (AU)

Processo FAPESP: 09/17611-7 - Glândulas florais e interações com polinizadores em Bignoniaceae de cerrado
Beneficiário:Elza Maria Guimarães Santos
Linha de fomento: Bolsas no Brasil - Pós-Doutorado
Processo FAPESP: 08/55434-7 - Estruturas secretoras em espécies vegetais de cerrado: abordagens morfológica, química e ecológica
Beneficiário:Silvia Rodrigues Machado
Linha de fomento: Auxílio à Pesquisa - Programa BIOTA - Temático