| Texto completo | |
| Autor(es): |
Pedersoli, Giseli D.
[1, 2]
;
Leme, Flavia M.
[3, 4]
;
Leite, Viviane G.
[1, 2]
;
Teixeira, Simone P.
[1]
Número total de Autores: 4
|
| Afiliação do(s) autor(es): | [1] Univ Sao Paulo, Fac Ciencias Farmaceut Ribeirao Preto, Ave Cafe S-N, BR-14040903 Ribeirao Preto, SP - Brazil
[2] Univ Sao Paulo, Fac Filosofia Ciencias & Letras Ribeirao Preto, Dept Biol, Ave Bandeirantes 3900, BR-14040901 Ribeirao Preto, SP - Brazil
[3] Univ Estadual Campinas, Inst Biol, R Monteiro Lobato 255, BR-13083862 Campinas, SP - Brazil
[4] Univ Fed Mato Grosso do Sul, Inst Biociencias, CP 549, BR-79070900 Campo Grande, MS - Brazil
Número total de Afiliações: 4
|
| Tipo de documento: | Artigo Científico |
| Fonte: | AMERICAN JOURNAL OF BOTANY; v. 106, n. 3, p. 489-506, MAR 2019. |
| Citações Web of Science: | 0 |
| Resumo | |
Premise of the StudyThis study details the unusual synorganization of the staminate flower in wind-pollinated urticalean rosids to add the missing pieces that complete the puzzle of the explosive mechanism of pollen release in this group. MethodsFlower buds and flowers were analyzed using light and scanning electron microscopy. Key ResultsThe pistillode, stamens, and sepals form a floral apparatus that explosively releases pollen to be carried by the wind. The anthers dehisce when the stamens are still inflexed on the floral bud and are enveloped by the sepals and supported by an inflated pistillode. The distension of the filaments presses the pistillode, which decreases the pressure exerted on the anthers by releasing the air accumulated internally through its apical orifice. The extended filaments and the dehiscent free anthers move rapidly outward from the center of the flower. This movement of the filaments is then blocked by the robust basally united sepals, which causes a rapid inversion of the anther position, thus hurling the pollen grains far from the flower. The pollen grains are released grouped by the mucilage produced in high quantity in the cells found in all floral organs. ConclusionsThe anatomical structure of the pistillode and the finding of mucilaginous cells are the main features that help in the understanding the explosive mechanism of pollen release in urticalean rosids. The pistillode can be considered an exaptation because it was evolved later to provide a new role in the plant, optimizing male fitness. (AU) | |
| Processo FAPESP: | 14/07453-3 - Desenvolvimento floral de espécies do clado urticoide |
| Beneficiário: | Simone de Pádua Teixeira |
| Modalidade de apoio: | Auxílio à Pesquisa - Regular |
| Processo FAPESP: | 12/15644-8 - Desenvolvimento da flor e da inflorescência de espécies de Moraceae |
| Beneficiário: | Viviane Gonçalves Leite |
| Modalidade de apoio: | Bolsas no Brasil - Doutorado |
| Processo FAPESP: | 13/19459-3 - Desenvolvimento floral de espécies de Urticaceae Juss. |
| Beneficiário: | Giseli Donizete Pedersoli |
| Modalidade de apoio: | Bolsas no Brasil - Doutorado |