Estruturas secretoras do gênero jatropha L. (Euphorbiaceae)

Abstract

The Euphorbiaceae family has outstanding anatomical characteristics that add important taxonomic value, for example, the secretory structures commonly found, such as trichomes, colleters and dairy products. This family is well represented in all regions of Brazil, including Bahia, with around 329 species. The genus Jatropha has about 170 species distributed in several continents, occupying the 5th place in terms of representativeness. This genre has been standing and showing that there is a growing interest for the relative scientific studies of this group. Jatropha curcas L. deserves prominence in the genus due to the production of oil in its seed, which is used in the production of biodiesel. The aim of this work was to describe the secretory structures of four J. curcas, J. gossypiifolia, J. martiusii, J. mollissima, and to characterize the secretions produced by them. The species were collected in the cities of Santa Teresinha - BA and Cruz das Almas - BA. The samples were submitted to fixation, serial dehydration of butyl alcohol, paraffin inclusion, stained and finally slides were assembled with the material. Part of the samples were fixed to obtain images in the scanning electron microscope. For histochemistry was used the histochemical tests protocol following the recommendation of each author. All species of anastomosed laticifers. The presence of a colleter evidenced by histochemical tests is a distinctive characteristic for Jatropha gossypiifolia. The species share the presence of phenolic compounds, proteins, lipids and polysaccharides and the absence of tannins and starch. Jatropha gossypiifolia is the only one without rubber and with alkaloids. The data obtained in this work, about the chemical substances of the species and the location of the structures that secrete them, may subsidize studies in popular medicine, pharmacology, taxonomy and ecology, also contributing to the anatomical and histochemical characterization in other species, genera or families of Angiosperms.