Anatomy and phytochemistry of Aldama La Llave (Asteraceae - Heliantheae)species

Abstract

Asteraceae is one of the largest families with 1,620 genus and approximately 23,600 species. It has cosmopolitan distribution and origin center in South American. The success of the family in occupying several environments is related to the occurrence of secondary metabolites, to the morphology of the inflorescence and efficient dispersal mechanisms, and to the morphological variability found in their representatives. Heliantheae tribe is the second largest tribe of the family, with 189 genus and 1,500 species. Viguiera sensu lato (Viguiera Kunth) is one of the largest genus in the tribe, with approximately 180 species, exclusively American and with diversity centers in Mexico, Andes and Brazilian plateaus. This is not a monophyletic group and molecular studies have been carried out in order to clarify the phylogenetic relationships into the genus. Recently, the South American species were transferred to Aldama genus, however there are errors and nomenclatural omissions in that paper and complementary studies are needed, considering that the circumscription of the South American species are not well established. Therefore, the aim of this study is to identify anatomical, morphological and chemical variations, which may be useful for distinguishing species. The species are Aldama bakeriana S.F. Blake E.E.Schill. & Panero (Viguiera bakeriana), A. discolor (Baker) E.E.Schill. & Panero (V. discolor), A. grandiflora (Gardner) E.E.Schill. & Panero (V. grandiflora) and A. squalida (S. Moore) E.E.Schill. & Panero (V. squalida), which are inserted in the same series (Grandiflorae) in the generic classification. They are endemic in Brazil and difficult to identify in vegetative state. It will be performed anatomical analyzes of the aerial and underground organs according to usual histological techniques, histochemical tests for detection of classes of compounds produced by these species and the synthesis sites of these compounds. Moreover, it will be performed analyzes in GC-SM and GC-FID to determine the chemical composition of the essential oils and extracts, obtained by hydrodistillation in Clevenger system and extraction with ethyl acetate, respectively.