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Guimarães Veloso D, de Freitas Mansano V, Pádua Teixeira S, Alcantara de Oliveira C, Baratto LC, Almeida Rodrigues I, Villela Paulino J. Unveiling foliar secreting sites and secretion composition in the legume tree Swartzia flaemingii Raddi. Chem Biodivers 2024; 21:e202301616. [PMID: 38161186 DOI: 10.1002/cbdv.202301616] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2023] [Revised: 12/28/2023] [Accepted: 12/31/2023] [Indexed: 01/03/2024]
Abstract
Secretory structures in plants play a crucial role in producing bioactive compounds. Despite the potential of the Swartzia genus, comprehensive studies in this context are still scarce. Swartzia is a legume tree (Fabaceae) that occurs in the Brazilian Atlantic Forest, a biodiversity hotspot, and includes species such as Swartzia flaemingii. Therefore, we aim to achieve: (1) identify and characterize the key secretory sites responsible for saponin production in S. flaemingii leaflets; (2) confirm the presence of saponins in S. flaemingii leaves by comparing them with known chemical profiles of other Swartzia species; (3) assess the potential hemolytic and cytotoxic effects of crude leaf extracts. Our investigation unveils the presence of phenolic idioblasts, mucilage cells, and articulate laticifers, which play pivotal roles in defense and adaptation. Notably, we report the first-ever ultrastructural details of laticifers in a legume species. Additionally, oleanane-type saponins were identified in the leaves, giving insights into the chemotaxonomic profile of Swartzia. The crude extracts show low cytotoxicity levels, showcasing as a promising alternative source of saponins. This investigation reinforces the importance of conserving plants in threatened regions like the Atlantic Forest, a global biodiversity hotspot facing substantial anthropogenic pressures.
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Affiliation(s)
- Dalton Guimarães Veloso
- Departamento de Produtos Naturais e Alimentos, Faculdade de Farmácia, Centro de Ciências da Saúde, Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, RJ 21941-902, Brazil
| | - Vidal de Freitas Mansano
- Instituto de Pesquisas Jardim Botânico do Rio de Janeiro, DIPEQ, Rua Pacheco Leão 915, Rio de Janeiro, RJ 22460-030, Brazil
| | - Simone Pádua Teixeira
- Departamento de Ciências Farmacêuticas, Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo (USP), Av. do Café, s/n., Ribeirão Preto, SP 14040-903, Brazil
| | - Carolina Alcantara de Oliveira
- Departamento de Produtos Naturais e Alimentos, Faculdade de Farmácia, Centro de Ciências da Saúde, Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, RJ 21941-902, Brazil
| | - Leopoldo C Baratto
- Departamento de Produtos Naturais e Alimentos, Faculdade de Farmácia, Centro de Ciências da Saúde, Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, RJ 21941-902, Brazil
| | - Igor Almeida Rodrigues
- Departamento de Produtos Naturais e Alimentos, Faculdade de Farmácia, Centro de Ciências da Saúde, Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, RJ 21941-902, Brazil
| | - Juliana Villela Paulino
- Departamento de Produtos Naturais e Alimentos, Faculdade de Farmácia, Centro de Ciências da Saúde, Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, RJ 21941-902, Brazil
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Rodrigues AM, Mendes AR, Caeiro MF, Figueiredo AC, Ascensão L. New Reports on the Portuguese Endemic Species, Santolina impressa: Secretory Structures, Essential Oil Composition and Antiviral Activity. Plants (Basel) 2023; 12:2391. [PMID: 37446952 DOI: 10.3390/plants12132391] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2023] [Revised: 06/13/2023] [Accepted: 06/16/2023] [Indexed: 07/15/2023]
Abstract
Santolina impressa is an aromatic Asteraceae species endemic to Portugal, traditionally used for its anti-inflammatory properties. The aim of this study was to characterize S. impressa secretory structures, analyze the essential oil (EO) from the aerial organs, and evaluate its antiviral activity against herpes simplex viruses HSV-1 and HSV-2. Secretory structures were investigated by light and scanning microscopy, and the secretion was histochemically characterized. The EO from the aerial organs in full blooming was analyzed by gas chromatography with flame ionization detection and gas chromatography-mass spectrometry. Antiviral assays were performed by direct contact with viral suspensions (virucidal effect), and in infected Vero E6 cells, at different time periods during the viral replication cycle. Two types of secretory structures were described, biseriate glandular trichomes and secretory ducts, producing an oleoresin and a resin rich in flavonoids, respectively. Fifty compounds were identified in S. impressa EO, accounting for 87% of the total constituents. Monoterpenes constituted the main EO fraction (82%), with β-pinene (13%) and β-phellandrene (10%) being their major components. The EO interacted with HSV-1 and HSV-2 in a dose-dependent manner, thereby inactivating both viral infections. The EO did not evidence a virucidal effect but inhibited the HSV-1 and HSV-2 infection in Vero cells in a dose-dependent manner. However, further studies are needed to investigate the mode of action in the replication cycle.
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Affiliation(s)
- Ana Margarida Rodrigues
- Centro de Estudos do Ambiente e do Mar (CESAM Lisboa), Faculdade de Ciências da Universidade de Lisboa (FCUL), DBV, C2, Campo Grande, 1749-016 Lisboa, Portugal
| | - Ana Rita Mendes
- Centro de Estudos do Ambiente e do Mar (CESAM Lisboa), Faculdade de Ciências da Universidade de Lisboa (FCUL), DBV, C2, Campo Grande, 1749-016 Lisboa, Portugal
| | - Maria Filomena Caeiro
- Centro de Estudos do Ambiente e do Mar (CESAM Lisboa), Faculdade de Ciências da Universidade de Lisboa (FCUL), DBV, C2, Campo Grande, 1749-016 Lisboa, Portugal
| | - Ana Cristina Figueiredo
- Centro de Estudos do Ambiente e do Mar (CESAM Lisboa), Faculdade de Ciências da Universidade de Lisboa (FCUL), DBV, C2, Campo Grande, 1749-016 Lisboa, Portugal
| | - Lia Ascensão
- Centro de Estudos do Ambiente e do Mar (CESAM Lisboa), Faculdade de Ciências da Universidade de Lisboa (FCUL), DBV, C2, Campo Grande, 1749-016 Lisboa, Portugal
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Naidoo D, Naidoo Y, Naidoo G, Kianersi F, Dewir YH. Histochemical Analysis and Ultrastructure of Trichomes and Laticifers of Croton gratissimus Burch. var. gratissimus (Euphorbiaceae). Plants (Basel) 2023; 12:772. [PMID: 36840119 PMCID: PMC9964807 DOI: 10.3390/plants12040772] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/24/2022] [Revised: 02/04/2023] [Accepted: 02/06/2023] [Indexed: 06/18/2023]
Abstract
Croton gratissimus (Lavender croton) possesses three distinct secretory structures. These include lepidote and glandular trichomes and non-articulated unbranched laticifers. The lepidote trichomes form a dense indumentum on the abaxial surface of the leaves and canopy the glandular trichomes. Although assumed to be non-glandular, transmission electron microscopy (TEM) indicated high metabolic activity within the stalk and radial cells. Glandular trichomes are embedded in the epidermal layer and consist of a single cell which forms a prominent stalk and dilated head. Laticifers occur on the mid-vein of leaves and are predominantly associated with vascular tissue. In the stems, laticifers are associated with the phloem and pith. Both trichome types and laticifers stained positive for alkaloids, phenolic compounds, and lipids. Positive staining for these compounds in lepidote trichomes suggests their involvement in the production and accumulation of secondary metabolites. These metabolites could provide chemical defense for the plant and potentially be useful for traditional medicine.
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Affiliation(s)
- Danesha Naidoo
- Department of Biological Sciences, School of Life Sciences, College of Agriculture, Engineering and Science, University of KwaZulu-Natal, Westville Campus, Private Bag X54001, Durban 4000, South Africa
| | - Yougasphree Naidoo
- Department of Biological Sciences, School of Life Sciences, College of Agriculture, Engineering and Science, University of KwaZulu-Natal, Westville Campus, Private Bag X54001, Durban 4000, South Africa
| | - Gonasageran Naidoo
- Department of Biological Sciences, School of Life Sciences, College of Agriculture, Engineering and Science, University of KwaZulu-Natal, Westville Campus, Private Bag X54001, Durban 4000, South Africa
| | - Farzad Kianersi
- School of Environmental Sciences, University of Guelph, 50 Stone Road East, Guelph, ON N1G 2W1, Canada
| | - Yaser Hassan Dewir
- Plant Production Department, College of Food & Agriculture Sciences, King Saud University, Riyadh 11451, Saudi Arabia
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Casique JV, Soares MVB, da Silva EF, Kikuchi TY, Andrade EHDA, Mastroberti AA. Coryanthes macrantha (Orchidaceae: Stanhopeinae) and their floral and extrafloral secretory structures: an anatomical and phytochemical approach. AoB Plants 2022; 14:plac039. [PMID: 36196392 PMCID: PMC9525647 DOI: 10.1093/aobpla/plac039] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/15/2022] [Accepted: 09/01/2022] [Indexed: 06/16/2023]
Abstract
Coryanthes is one of the most fascinating genera of Stanhopeinae (Orchidaceae) because of its complex pollination mechanism and the peculiar structures of its flowers. Although Coryanthes macrantha is widely studied, investigation of the secretory structures and floral biology is important to understand the mechanisms and ecology of pollination, which deserve attention despite the difficulties of collecting fertile material in nature. We conducted a morpho-anatomical analysis of the floral and extrafloral secretory structures of C. macrantha to better understand the secretory structures, contribute to the knowledge of its floral biology and/or pollination processes and understand the ecological function of these structures. The analysis revealed that C. macrantha has epidermal osmophores with unicellular papillae that were foraged by male Eulaema bees, floral nectaries in the sepals and extrafloral nectaries in the bracts. In both the floral and extrafloral nectaries, the nectar is exuded by the stomata. Azteca ants foraged the bract and sepal nectaries in pre-anthesis and post-anthesis. We also described the secretory epidermis of pleuridia, and the mode of secretion of osmophores and nectaries and found that they attract specific foraging agents.
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Affiliation(s)
- Jorgeane Valéria Casique
- Programa de Pós-graduação em Botânica, Departamento de Botânica, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS 91501-970, Brazil
| | - Marcos Vinícius Batista Soares
- Programa de Pós-graduação em Botânica, Departamento de Botânica, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS 91501-970, Brazil
| | - Edilson Freitas da Silva
- Programa de Pós-Graduação em Biodiversidade (Bionorte), Departamento de Botânica, Museu Paraense Emílio Goeldi, Belém, PA 66077-830, Brazil
| | - Tatiani Yuriko Kikuchi
- Instituto de Botânica, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ 21941-901, Brazil
| | - Eloisa Helena de Aguiar Andrade
- Programa de Pós-Graduação em Biodiversidade (Bionorte), Departamento de Botânica, Museu Paraense Emílio Goeldi, Belém, PA 66077-830, Brazil
| | - Alexandra Antunes Mastroberti
- Programa de Pós-graduação em Botânica, Departamento de Botânica, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS 91501-970, Brazil
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Rosa AC, Ferraro A, da Silva RH, Pott VJ, Victório CP, Arruda RDCDO. Leaf anatomy of two medicinal Croton species: Contribution to plant recognition. Microsc Res Tech 2021; 84:1685-1695. [PMID: 33580993 DOI: 10.1002/jemt.23727] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2020] [Revised: 01/10/2021] [Accepted: 01/26/2021] [Indexed: 11/10/2022]
Abstract
Croton L. (Euphorbiaceae) is the second largest genus of the Euphorbiaceae s.l. family, which is composed of about 1,200 taxa. Several species are widely used medicinally in various parts of the world to treat cancer, digestive problems, skin diseases, malaria, ulcers, and obesity. The leaves and stems are sold as dehydrated fragments, or in powder form, and used in the preparation of teas and various types of formulations. The aim of this study was to accurately characterize the leaf anatomy of Croton bonplandianus Baill. and Croton gracilipes Baill. and to perform histochemical analysis of laticifers to provide subsidies for botanical certification. To accomplish this, leaf blade and petiole samples were fixed and prepared following standard techniques for scanning electron and light microscopy. Histochemical tests were carried out on sections to detect the compounds present in the secretions. Results showed neutral and acidic lipids, as well as phenolic compounds, in the latex. In addition, leaf anatomical structures of these two species were studied for specific identification of morphological characters and for quality assessment of these medicinal plants.
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Affiliation(s)
- Aline Camargo Rosa
- Programa de Pós-Graduação em Biologia Vegetal, Universidade Federal de Mato Grosso do Sul, Campo Grande, Mato Grosso do Sul, Brazil
| | - Alexandre Ferraro
- Programa de Pós-Graduação em Biologia Vegetal, Universidade Estadual de Campinas, Campinas, Sao Paulo, Brazil
| | - Rosa Helena da Silva
- Laboratório de Ecologia Vegetal, Instituto de Biociências, Universidade Federal de Mato Grosso do Sul, Campo Grande, Mato Grosso do Sul, Brazil
| | - Vali Joana Pott
- Laboratório de Ecologia Vegetal, Instituto de Biociências, Universidade Federal de Mato Grosso do Sul, Campo Grande, Mato Grosso do Sul, Brazil
| | - Cristiane Pimentel Victório
- Laboratório de Pesquisa em Biotecnologia Ambiental, Fundação Centro Universitário Estadual da Zona Oeste (UEZO), Campo Grande, Rio de Janeiro, Brazil
| | - Rosani do Carmo de Oliveira Arruda
- Laboratório de Anatomia Vegetal, Instituto de Biociências, Universidade Federal de Mato Grosso do Sul, Campo Grande, Mato Grosso do Sul, Brazil
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Pace MR, Cunha Neto IL, Santos-Silva LNN, Melo-de-Pinna GFA, Acevedo-Rodríguez P, Almeida RF, Amorim AM, Angyalossy V. First report of laticifers in lianas of Malpighiaceae and their phylogenetic implications. Am J Bot 2019; 106:1156-1172. [PMID: 31517989 DOI: 10.1002/ajb2.1350] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/10/2019] [Accepted: 06/24/2019] [Indexed: 06/10/2023]
Abstract
PREMISE Laticifers have evolved multiple times in angiosperms and have been interpreted as a key innovation involved in plant defense mechanisms. In Malpighiaceae, laticifers were previously known from a single lineage of trees and shrubs, the Galphimia clade, but with detailed anatomical analyses here, we show that their distribution is broader in the family, also encompassing large clades of lianas. METHODS From 15 genera, 70 species of Malpighiaceae were surveyed through careful anatomical ontogenetic analysis of roots, stems, and leaves and detailed histochemical tests to elucidate the nature of laticifers and latex in the family. RESULTS Articulated anastomosing laticifers were encountered in roots, stems, and leaves of two distantly related megadiverse genera of Malpighiaceae lianas: Stigmaphyllon (stigmaphylloid clade) and Tetrapterys s.s. (tetrapteroid clade). From the apex downward, in Stigmaphyllon the laticifers are derived from the procambium and from the cambium during its early activity and are present in the outermost part of the vascular cylinder of stems and leaves and in the pericycle of roots, whereas in Tetrapterys s.s. they are derived from the ground meristem, procambium, and cambium throughout the plant body and are present in the cortex and pith, either the pericycle in roots or the outermost part of the vascular system in stems and leaves, and the primary and secondary phloem. CONCLUSIONS Laticifers seem to have evolved at least three times independently in Malpighiaceae, once in a lineage of trees and shrubs and twice in two distantly related megadiverse lianescent lineages. Laticifer evolution in Malpighiaceae is homoplastic and may be related to increases in species diversification.
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Affiliation(s)
- Marcelo R Pace
- Departamento de Botánica, Instituto de Biología, Universidad Nacional Autónoma de México, Circuito Zona Deportiva s.n., Ciudad Universitaria, Coyoacán, Mexico City, 04510, Mexico
- Department of Botany, National Museum of Natural History, Smithsonian Institution, Constitution Avenue & 10th Street NW, MRC-166, Washington, D.C., 20560, USA
| | - Israel L Cunha Neto
- Departamento de Botânica, Instituto de Biociências, Universidade de São Paulo, Rua do Matão, 277, Cidade Universitária, 05508-090, São Paulo, SP, Brazil
| | - Leyde N N Santos-Silva
- Departamento de Botânica, Instituto de Biociências, Universidade de São Paulo, Rua do Matão, 277, Cidade Universitária, 05508-090, São Paulo, SP, Brazil
| | - Gladys F A Melo-de-Pinna
- Departamento de Botânica, Instituto de Biociências, Universidade de São Paulo, Rua do Matão, 277, Cidade Universitária, 05508-090, São Paulo, SP, Brazil
| | - Pedro Acevedo-Rodríguez
- Department of Botany, National Museum of Natural History, Smithsonian Institution, Constitution Avenue & 10th Street NW, MRC-166, Washington, D.C., 20560, USA
| | - Rafael F Almeida
- Departamento de Botânica, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Avenida Antonio Carlos, 6627, 31270-901, Belo Horizonte, MG, Brazil
| | - André M Amorim
- Departamento de Ciências Biológicas, Universidade Estadual de Santa Cruz, km 25, Ilhéus-Itabuna, Ilhéus, Bahia, 45662-900, Brazil
- Herbário Centro de Pesquisa do Cacau, CEPEC, km 22, Rodovia Ilhéus-Itabuna, Itabuna, Bahia, 45600-970, Brazil
| | - Veronica Angyalossy
- Departamento de Botânica, Instituto de Biociências, Universidade de São Paulo, Rua do Matão, 277, Cidade Universitária, 05508-090, São Paulo, SP, Brazil
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Tölke ED, Bachelier JB, de Lima EA, Ferreira MJP, Demarco D, Carmello-Guerreiro SM. Osmophores and floral fragrance in Anacardium humile and Mangifera indica (Anacardiaceae): an overlooked secretory structure in Sapindales. AoB Plants 2018; 10:ply062. [PMID: 30402215 PMCID: PMC6215388 DOI: 10.1093/aobpla/ply062] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/18/2018] [Accepted: 10/04/2018] [Indexed: 05/07/2023]
Abstract
Flowers of Anacardiaceae and other Sapindales typically produce nectar, but scent, often associated with a reward for pollinators, has surprisingly been mentioned only rarely for members of the family and order. However, flowers of Anacardium humile and Mangifera indica produce a strong sweet scent. The origin and composition of these floral scents is the subject of this study. Screening of potential osmophores on the petals and investigations of their anatomy were carried out by light, scanning and transmission electron microscopy. The composition of the floral fragrance was characterized by gas chromatography-mass spectrometry. In both species, the base of the adaxial side of each petal revealed specialized secretory epidermal cells which are essentially similar in structure and distinct from all other neighbouring cells. These cells also showed evidence of granulocrine secretory mechanisms and slight specific variations in their subcellular apparatus coinciding with the respective composition of the floral fragrance, predominantly composed of sesquiterpenes in A. humile and monoterpenes in M. indica. This study reports the presence of osmophores for the first time in flowers of Anacardiaceae and confirms the link between the ultrastructural features of their secretory cells and the volatiles produced by the flowers. The flowers of most Sapindales, including Anacardiaceae, are nectariferous. However, the presence of osmophores has only been described for very few genera of Rutaceae and Sapindaceae. Both the occurrence of osmophores and fragrance may have largely been overlooked in Anacardiaceae and Sapindales until now. Further studies are needed to better understand the nature and diversity of the interactions of their nectariferous flowers with their pollinators.
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Affiliation(s)
- Elisabeth Dantas Tölke
- Departamento de Biologia Vegetal, Instituto de Biologia, Universidade Estadual de Campinas – UNICAMP, CEP Campinas, São Paulo, Brazil
| | - Julien B Bachelier
- Institute of Biology, Structural and Functional Plant Diversity Group, Freie Universität Berlin, Altensteinstrasse, Berlin, Germany
| | - Elimar Alves de Lima
- Departamento de Biologia Vegetal, Instituto de Biologia, Universidade Estadual de Campinas – UNICAMP, CEP Campinas, São Paulo, Brazil
| | - Marcelo José Pena Ferreira
- Departamento de Botânica, Instituto de Biociências, Universidade de São Paulo, CEP 05508-090 São Paulo, São Paulo, Brazil
| | - Diego Demarco
- Departamento de Botânica, Instituto de Biociências, Universidade de São Paulo, CEP 05508-090 São Paulo, São Paulo, Brazil
| | - Sandra Maria Carmello-Guerreiro
- Departamento de Biologia Vegetal, Instituto de Biologia, Universidade Estadual de Campinas – UNICAMP, CEP Campinas, São Paulo, Brazil
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Souza CD, Pereira RAS, Marinho CR, Kjellberg F, Teixeira SP. Diversity of fig glands is associated with nursery mutualism in fig trees. Am J Bot 2015; 102:1564-77. [PMID: 26419809 DOI: 10.3732/ajb.1500279] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/12/2015] [Accepted: 08/21/2015] [Indexed: 05/04/2023]
Abstract
PREMISE OF THE STUDY Fig trees (Moraceae) have remarkable enclosed inflorescences called figs or syconia. The flowers are pollinated by host-specific fig wasps that enter the fig to lay their eggs. This nursery pollination system is one of the most studied of tropical mutualism interactions, but the source of the volatiles that attract fig wasps to their specific host figs has not been confirmed. The fragrance is the basis of host selection and, therefore, of reproductive isolation among sympatric Ficus species. This study locates and characterizes the glands likely to be responsible for pollinator attraction and also protection from herbivory in the figs of nine Ficus species representing all the major lineages within the genus. METHODS Figs with receptive pistillate flowers were examined using light and scanning electron microscopy. Tests for histolocalization of substances were employed to detect glandular activity throughout the figs. KEY RESULTS A great diversity of glands is found throughout the fig, and for the first time, the sites producing fragrances are identified. Scent glands are present on the ostiolar bracts and the outer layers of the fig receptacle. Laticifers and phenolic-producing idioblasts, epidermis, and trichomes associated with fig protection occur on the ostiolar bracts, the fig receptacle, and floral tissues. CONCLUSIONS The volatiles produced by glands on the ostiolar bracts are candidate sources for the long-distance attraction of pollinator fig wasps. Scent glands on the outer layers of the receptacle may also play a role in chemical perception of the figs or may be related to their protection. The high cost to the plants if the figs are eaten and the temperature conditions required for nursery pollination are likely the factors that led to the selection of phenolic glands and laticifers during the group's evolution.
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Affiliation(s)
- Camila D Souza
- PPG em Biologia Comparada, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Av. Bandeirantes, 3900 - 14040-901, Ribeirão Preto/ SP, Brazil Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Av. do Café, s/n - 14040-903, Ribeirão Preto/ SP, Brazil
| | - Rodrigo A S Pereira
- Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Av. Bandeirantes 3900 - 14040-903, Ribeirão Preto/ SP, Brazil
| | - Cristina R Marinho
- Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Av. do Café, s/n - 14040-903, Ribeirão Preto/ SP, Brazil
| | - Finn Kjellberg
- CEFE UMR 5175, CNRS-Université de Montpellier-Université Paul-Valéry Montpellier-EPHE, 1919 route de Mende, F-34293 Montpellier Cédex 5, France
| | - Simone P Teixeira
- Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Av. do Café, s/n - 14040-903, Ribeirão Preto/ SP, Brazil
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Dalvi VC, Meira RMSA, Azevedo AA. Extrafloral nectaries in neotropical Gentianaceae: occurrence, distribution patterns, and anatomical characterization. Am J Bot 2013; 100:1779-1789. [PMID: 24008515 DOI: 10.3732/ajb.1300130] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
PREMISE OF THE STUDY Extrafloral nectaries (EFNs) are structures that secrete nectar and protect plants against herbivores and pathogens. In Gentianaceae, these structures have been described in species of Calolisianthus, Fagraea, and Anthocleista and are important morphological markers for taxonomic and phylogenetic studies. To establish a foundation for further studies, we investigated the occurrence, distribution patterns, and anatomy of EFNs on leaves of 27 species belonging to 13 genera and three tribes of neotropical Gentianaceae. • METHODS Leaf samples were diaphanized, stained with basic fuchsin, and mounted in glycerinated gelatin. Cross sections were obtained from material embedded in methacrylate or paraffin, stained, and mounted in Permount. Polysaccharides were histochemically stained with periodic acid-Schiff stain. Samples were also examined with scanning electron microscopy. • KEY RESULTS Unusual EFNs, visible only with light microscopy, were formed of modified epidermal cells. Each EFN consisted of 2-5 secretory cells encircling a central cell. The EFNs varied in size and in the shape and arrangement of the adjacent cells surrounding the secretory cells. EFNs occurred in all analyzed species as isolated units distributed throughout the leaf blade or as aggregates; aggregates were generally visible to the naked eye. Based on their occurrence as aggregates or isolated units and on their location on the leaf blade, six distribution patterns were identified. • CONCLUSIONS This is the first comprehensive study of EFNs on the leaves of neotropical Gentianaceae. The data suggested that NEFs evolved from isolated units for NEFs in aggregates. The results represent a new source of data for future ecological, systematic, and phylogenetic studies in Gentianaceae.
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Affiliation(s)
- Valdnéa Casagrande Dalvi
- Departamento de Biologia Vegetal, Universidade Federal de Viçosa (UFV), Av. P.H. Rolfs, s/n, Campus Universitário, CEP 36570-000, Viçosa, Minas Gerais, Brasil
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