| Abstract Detail
Developmental and Structural Section Bombo, Aline Bertolosi [1], Farias, Leticia Onofre de [2], Rehder, Vera Lucia Garcia [2], Appezzato-da-Gl�ria, Beatriz [1]. Anatomy and phytochemistry of the leaves of an endemic Brazilian species of Aldama (Asteraceae, Heliantheae). The South American species of Aldama have already been included in Viguiera sensu lato, which is demonstrably a non monophyletic group. However, despite new combinations presented for the most of the Brazilian species, the circumscription of South American species is not well established yet. This study aimed to enrich the knowledge of Brazilian species of Aldama and is included in a thematic project whose one of the purposes is to indentify anatomical characteristics that could help in the taxonomical resolution of these species. Aldama grandiflora is an endemic Brazilian species which occurs in Cerrado areas (Brazilian savannah). Its representatives are from herbaceous to sub-shrubs, having a thickened underground stem with tuberous adventitious roots. Samples were collected from one population in Brasilia-DF and from two populations in Alto Paraíso de Goiás-GO). The first one is located at different latitude from the other two populations. For the anatomical analysis, fully expanded leaves were analyzed from three individuals per population and the samples were processed according to usual techniques in plant anatomy. The essential oils were obtained by hydrodistillation in a Clevenger-type apparatus, analysed by gas chromatography coupled with mass spectrometry and the compounds were identified by comparing the mass spectra with library data. An extraction was performed to each population. The leaf is characterized by uniseriate epidermis with thickened outer walls enriched in pectins with straight cells walls from the front side view, anomocytic stomata, presence of three types of trichomes, secretory ducts associated to the sheath extensions of the vascular bundles and to the phloem, and hydathodes in the ornamentations of the leaf margins. The distribution of the secretory ducts varied among the individuals into the population and also among the populations. Histochemical tests detected the presence of lipophilic substances, terpenes, pectin, mucilage and phenolic compounds, mainly in secretory ducts and trichomes. The analysis of essential oil showed differences amongst populations, mainly in compounds of lower relative percentages and some compounds that were not reported to Aldama species before (terpinolen, δ-amorphene, globulol, eudesmol and α-eudesmol) were identified. The variations observed in the distribution of the secretory structures and in the chemical composition of the essential oil among the populations indicate that environmental and geographical differences that these populations are undergoing are very important to the determination of the phenotype and, therefore, studies with individuals from different populations are needed for the correct characterization of the species. Broader Impacts:
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Related Links:
Website of the Thematic project supported by FAPESP
1 - University of Sao Paulo, Biological Sciences , 11 Padua Dias Avenue, Piracicaba, SP, 13418900, Brasil
2 - University of Campinas, Chemical, Biological and Agricultural Pluridisciplinary Research Center, 999 Alexandre Cazelatto street, Paulinia, SP, 13081-970, Brasil
Keywords:
secretory structures
Viguiera
essential oil
chemical composition
foliar anatomy
trichomes.
Presentation Type: Poster:Posters for Sections
Session: P
Location: Grand Salon A - D/Riverside Hilton
Date: Monday, July 29th, 2013
Time: 5:30 PM
Number: PDS002
Abstract ID:116
Candidate for Awards:Katherine Esau Award |
