Article

Download article 		Title: Diversity of floral nectary secretions and structure, and implications for their evolution in Anacardiaceae
Author: Tölke, Elisabeth D; Bachelier, Julien B; Lima, Elimar A; Galetto, Leonardo; Demarco, Diego; Carmello-guerreiro, Sandra M
Year: 2018
Is part of: BOTANICAL JOURNAL OF THE LINNEAN SOCIETY, v. 187, p. 209 - 231
DOI: https://doi.org/10.1093/botlinnean/boy016

Citation: Tölke, Elisabeth D; Bachelier, Julien B; Lima, Elimar A; Galetto, Leonardo; Demarco, Diego; Carmello-guerreiro, Sandra M; Diversity of floral nectary secretions and structure, and implications for their evolution in Anacardiaceae. BOTANICAL JOURNAL OF THE LINNEAN SOCIETY, v.187, p. 209-231, 2018

Abstract: The flowers of most Anacardiaceae have a floral nectary disk producing nectar rich in sugars. However, a recent study demonstrated that their nectaries might also produce other substances, including lipids and phenolic compounds. To explore the diversity of floral nectary production and (ultra)structure, and their potential for the systematics of Anacardiaceae, we studied seven genera and 13 species from the two subfamilies. We used spectrophotometry to identify sugars and histochemical tests for other substances, and electron and brightfield microscopy to study nectary (ultra)structure and secretory pathways. The composition of sugars and other substances can vary between closely related species and be more similar in species from different subfamilies, being of limited value for the systematics of the family. The general morphology and structure of the floral nectary and their secretory pathways appear to be conservative in the family, and, like the production of mixed secretions, they might be plesiomorphic. Three morphological types of floral nectaries are defined for the family: nectariferous disk with papillose (1) or smooth epidermis-type (2) and trichomatous-type (3). The secretions may be released both by granulocrine and eccrine mechanisms and exuded through nectarostomata or the cuticle. Further studies are needed to better understand their evolutionary and ecological implications in Anacardiaceae and other sapindalean lineages.


Subjects: CIENCIAS_BIOLOGICAS; botânica; CIENCIAS_BIOLOGICAS; Botânica; Morfologia Vegetal; Anatomia Vegetal;

Funding: The authors thank CAPES (Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior) and CNPq (Conselho Cientifico de Desenvolvimento Cientifico e Tecnologico) for the PhD scholarship to EDT, granted during the development of this work. We also thank CAPES for the scholarship provided for EDT during a semester abroad at FU Berlin (PDSE proc. no 88881.133676/2016-01). This research was financially supported by grants from 'Fundacao de Amparo a Pesquisa do Estado de Sao Paulo' (FAPESP - proc. no 2014/18002-2), CNPq (proc. no 420417/2016-8) and CONICET (Consejo Nacional de Investigaciones Cientificas y Tecnicas, PIP 11220120100055CO), SECyT (Secretaria de Ciencia y Tecnologia de la Universidad Nacional de Cordoba, UNC 05/I591) and FONCyT (Fondo para la Investigacion Cientifica y Tecnologica de la Agencia Nacional de Promocion Cientifica y Tecnologica, PICT-2015- 0538). We are grateful to Moritz Mittelbach for insightful discussions on nectars and Theodor C.H. Cole for help with language editing and valuable comments. 		Financed by: