Structural variations among monocot emergent and amphibious species from lakes of the semi-arid region of Bahia, Brazil.

Temporary lakes are common in the semi-arid region of the State of Bahia and form water mirrors in the rainy season. In this period, various vegetal species appear having different life forms adapted to the seasonality conditions of the rainfall regime. This work surveyed the adaptive anatomical structures of some emergent and amphibious monocot species occurring in these lakes. We studied the anatomy of roots, rhizomes, leaves and scapes of Cyperus odoratus, Oxycaryum cubense, Pycreus macrostachyos (Cyperaceae) - amphibious species; and of Echinodorus grandiflorus (Alismataceae), Eichhornia paniculata (Pontederiaceae) and Habenaria repens (Orchidaceae) - emergent species. The anatomical features of the dermal, fundamental and vascular systems confirming the tendency of the adaptive convergence of these plants to temporary lacustrine the environment include: single layered epidermal cells with a thin cuticle layer in the aerial organs; the presence of air canals in all the organs; few or no supporting tissues; and less numerous conducting elements and thinner cell walls in the xylem. The reduction of the supporting tissues, the number of stomata, which can even be absent, and the number of conducting elements and the degree of cell wall lignification in the xylem of the emergent species is more accentuated than that of the amphibious species. The pattern of distribution of aerenchyma in the roots of the studied species was considered important to distinguish between amphibious and emergent life forms.

Comparative analysis of the leaf anatomy in two Parodiolyra species (Poaceae: Olyreae) occurring on forests in Eastern Brazil.

Parodiolyra is a member of Olyreae, a tribe of herbaceous bamboo species within the Poaceae. The genus has five species, four of which were previously regarded as belonging to Olyra L. Parodiolyra has a Neotropical distribution and only two species occur on forests in Eastern Brazil: P. micrantha (Kunth) Zuloaga & Davidse and P. ramosissima (Trin.) Soderstr. & Zuloaga, the first widely distributed in the Neotropics while the second is endemic to the state of Bahia. Leaf anatomy of the two species was analysed with the aid of an optical microscope. The objective was to describe the microscopic characters and evaluate if they can be useful for the taxonomy of the genus. The observed anatomical structures did not differ from other genera of herbaceous bamboos, however some characters, both from the mesophyll and the epidermis, were useful to delimit the two species.

Anatomia dos órgãos vegetativos de Hymenaea martiana Hayne (Caesalpinioideae-Fabaceae): espécie de uso medicinal em Caetité-BA / Anatomy of vegetative organs of Hymenaea martiana Hayne (Fabaceae-Caesalpinioideae): a species of medicinal use in Caetité-Bahia State, Brazil

Hymenaea martiana Hayne (Fabaceae-Caesalpinioideae) apresenta grande valor na medicina popular em Caetité. A casca, entrecasca do caule e a resina, são utilizadas no tratamento de diversos males. Neste estudo são apresentadas a caracterização anatômica e histoquímica dos órgãos vegetativos. Amostras foram coletadas e processadas segundo técnicas usuais em anatomia vegetal e histoquímica. Todos os órgãos apresentam, em visão transversal, epiderme unisseriada e cavidades secretoras. Cutícula espessa ocorre em todos os órgãos aéreos. A raiz é tetrarca. Colênquima lacunar foi encontrado no caule. Bainha de fibras esclerenquimáticas envolve os feixes vasculares dos órgãos aéreos. Células pétreas ocorrem no pecíolo. Tricomas tectores ocorrem em ambas as faces da folha. A folha é hipoestomática com estômatos paracíticos e o mesofilo é dorsiventral. Cristais de oxalato de cálcio ocorrem no caule, pecíolo e lâmina foliar. Compostos fenólicos ocorrem na raiz, pecíolo e nervura central da folha. Grãos de amido ocorrem na raiz, caule e pecíolo. Lipídios ocorrem em todos os órgãos. Acredita-se que compostos fenólicos e cavidades secretoras de resina podem justificar a utilidade medicinal da espécie pela população de Caetité.

Hymenaea martiana Hayne (Fabaceae-Caesalpinioideae) shows a great value in folk medicine in Caetité. Its bark, stem-bark and resin are used to treat various ailments. In this study, the anatomical and histochemical characterization of vegetative organs is reported. Samples were collected and processed according to usual techniques of plant anatomy and histochemistry. All organs have, by cross-sectional view, uniseriate epidermis and secretory cavities. Thick cuticle occurs in all aerial organs. The root is tetrarch. Lacunar collenchyma was found in the stem. Sclerenchymatic sheath of fibers surrounds the vascular bundles of the aerial organs. Stone cells occur in the petiole. Trichomes occur on both sides of the leaves. The leaf is hypostomatic with paracytic stomata and the mesophyll is dorsiventral. Calcium oxalate crystals occur in the stem, petiole and leaf blade. Phenolic compounds occur in the root, petiole and midrib of the leaf. Starch grains occur in the root, stem and petiole. Lipids occur in all organs. It is believed that phenolic compounds and resin secretory cavities may justify the use of medicinal species by the population of Caetité.