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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.)

Ontogeny and Vascularization Elucidate the Atypical Floral Structure of Ampelocera glabra, a Tropical Species of Ulmaceae

Texto completo
Leme, Flavia M. [1, 2, 3] ; Staedler, Yannick M. [4] ; Schonenberger, Jurg [4] ; Teixeira, Simone P. [1]
Número total de Autores: 4
Afiliação do(s) autor(es):
[1] Univ Sao Paulo, Fac Ciencias Farmaceut Ribeirao Preto, Dept Ciencias Farmaceut, Ave Cafe S-N, BR-14040903 Sao Paulo - Brazil
[2] Univ Estadual Campinas, Programa Posgrad Biol Vegetal, Inst Biol, Rua Monteiro Lobato 255, BR-13083862 Sao Paulo - Brazil
[3] Univ Fed Mato Grosso do Sul, Inst Biociencias, Cidade Univ, CP 549, BR-79002970 Campo Grande, MS - Brazil
[4] Univ Vienna, Dept Bot & Biodivers Res, Rennweg 14, AT-1030 Vienna - Austria
Número total de Afiliações: 4
Tipo de documento: Artigo Científico
Fonte: INTERNATIONAL JOURNAL OF PLANT SCIENCES; v. 179, n. 6, p. 461-476, JUL-AUG 2018.
Citações Web of Science: 2

Premise of research.Ampelocera glabra is an andromonoecious, wind-pollinated species of Ulmaceae, the elm family. This family comprises two clades: tropical and temperate. The species that have been morphologically studied so far all belong to the temperate clade. Ampelocera glabra is included in the tropical clade and is remarkable due to its atypical flower merism when compared to other Ulmaceae and to most other rosids: tetramerous calyx, polyandrous androecium, and pseudomonomerous gynoecium. Thus, our objective was to study the ontogeny and vascularization of the A. glabra flower to elucidate the processes involved in the atypical merism and in the reduced structure of the whorls. Additionally, the mating system of A. glabra was checked and its floral structure was associated with anemophily, thus contributing to reproductive studies of this species under threat of extinction.Methodology.Flowers and early to late floral buds were processed for surface (SEM) and histological (LM) investigations and 3D reconstructions (X-ray microcomputed tomography).Pivotal results.Ampelocera glabra is actually a monoecious species with functionally staminate and functionally pistillate flowers, containing carpellodes and staminodes, respectively. The single perianth whorl is composed of sepals, and there is no hypanthium. Each primordium of the sepals and stamens arises individually. A central common primordium gives rise to two carpels, but only one houses an ovule. Each carpel is vascularized by one dorsal bundle, and the carpel that bears the ovule is also vascularized by one ventral bundle. Thus, the gynoecium displays a reduction in the vascular bundle in the nonovulate carpel.Conclusions.The differences in merism between the calyx and the androecium are explained by the space that can support the increase in organ number. The increase in stamen number and the reduced gynoecium (pseudomonomerous) enable a high pollen:ovule ratio, which is an important condition for any anemophilous species. (AU)

Processo FAPESP: 14/07453-3 - Desenvolvimento floral de espécies do clado urticoide
Beneficiário:Simone de Pádua Teixeira
Linha de fomento: Auxílio à Pesquisa - Regular