The lauraceae collected in brazil by ludwig riedel - I

The species of Lauraceae collected by Ludwig Riedel, excluding Ocotea, are commented and contex-tualized according to the different itineraries he travelled in Brazil, from 1821 to 1836, indicating the localities and dates of collections, whenever possible. To complete this work, two diaries of Riedel have been consulted and the information from them cross-checked with the annotations found on specimen labels. An annotated list of 48 entries provides information on the status of species names and their types, currently accepted names, and collections found in different herbaria. Lectotypes for five names, Aydendron verrucosum var. attenuata, Aydendron parviflorum, Mespilodaphne parviflora, Nectandra spicata, and Oreodaphne fasciculata, are designated. The species of Ocotea collected by Riedel will be treated in part II of this series. © President and Fellows of Harvard College, 2012.

The lauraceae collected in brazil by ludwig riedel - II. Ocotea

The species of Ocotea (Lauraceae) collected by Ludwig Riedel are commented and contextualized according to the different itineraries he travelled in Brazil, from 1821 to 1836, indicating the localities and dates of collections, whenever possible. To complete this work, two diaries of Riedel have been consulted and the information from them crossed-checked with the annotations found on specimen labels. An annotated list of 44 entries provides information on the status of species names and their types, currently accepted names, and collections found in different herbaria. Lectotypes for 19 names are designated, two new synonyms are proposed, as well as the new combination Ocotea estrellensis (Meisn.) P.L.R. Moraes, based on Oreodaphne estrellensis Meisn. © President and Fellows of Harvard College, 2012.

Termos botânicos

Há termos botânicos que são heterofônicos. O significado e a perfeita prosadia doles obém-se em linguagem científica, através da etimologia. Como exemplo,encontram-se mesofilo e mesófilo. Este, sendo proparoxítono, refere-se aquilo que vive em lugares de luz difusa e umidade média; e aquale, referindo-se a anatomia da folha, é paroxítono. Com relação ao termo taxinomia, formado pelos prefixos gregos taxi e namo e mais o sufixo -ia, não deixa de ser a melhor combinação e deve-se, portanto, rejeitar as formas paralelas de taxeonomia, taxionomia e taxonomia.

Five new species of Ocotea (lauraceae) from Bahia, Brazil

Five South-American species of the genus Ocotea from Bahia, Brazil, are described and illustrated. The new species are Ocotea adamantina, O. rohweri, O. sperata, O. thinicola, and O. vegrandis. Their relationships within the genus are discussed. © President and Fellows of Harvard College, 2011.

Three new taxa of meliosma (Sabiaceae) neotropical sabiaceae: Three new species and a new variety of meliosma

Three new neotropical species of Sabiaceae, M. robusta from Peru, M. starkii from Mexico, Meliosma cornejoi, and a new variety, M. boliviensis var. sumacensis from Ecuador, are here described and illustrated. © President and Fellows of Harvard College, 2012.

Léxico e cores: as expressões cromáticas contribuindo para a ampliação lexical

The lexicon is the cultural heritage of a people. It is composed by the linguistic and extra-linguistic experience gained over the years and consists of different systems, among them the lexical set of colors that has collaborated on lexical expansion in common discourse as well as in specialized discourse, providing the interaction and equilibrium among the different levels of specialization of discourse. This work aims at talking about the role of the field of colors in formation of new lexical units in Botany and Zoology, as well as its performance in the intersection between the common and specialized discourse.

A mulher na botânica: questões de gênero na participação feminina em congressos de botânica no Brasil

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

A scanning electron microscopy study of the seed and post-seminal development in Angelonia salicariifolia Bonpl. (Scrophulariaceae)

The external morphology of seeds and post-germination developmental stages of Angelonia salicariifolia Bonpl. (Scrophulariaceae) were investigated using scanning electron microscopy. Some structural features of the seed exotesta and seedling in Angelonia are presented for the first time and are of potential taxonomic value for this neotropical genus. The seeds are very small (0.9-1.7 mm long and 0.5-0.9 mm wide), ovate, with a reticulate-crested exotesta, reticules arranged uniformly in longitudinal rows, with a high density of microcilia-like projections on the cell wall of the reticule base and on the edge of the crests. The hilum is located beside the micropyle at the narrow end of the seed. Germination is epigeal. During germination the radicle develops, followed by elongation of the hypocotyl and primary root. At this stage dense root hairs develop on the lower part of the hypocotyl. The apical bud-located between the cotyledons-begins to develop after the cotyledons have unfolded. The cotyledons are equal in size, sessile and ovate. The seedlings have two types of trichomes, one characteristic of the cotyledons and first pair of leaves (glandular, sessile, four-celled head with quadrangular shape) and the other characteristic of the hypocotyl and epicotyl (stalked, erect, elongate and three-celled with dome-shaped unicellular head). (C) 2001 Annals of Botany Company.

Photosynthetic induction in Eucalyptus urograndis seedlings and cuttings measured by an open photoacoustic cell

Photosynthetic induction in leaves of four-month-old Eucalyptus urograndis seedlings and of cuttings obtained from adult trees that were previously dark-adapted was studied by the in vivo and in situ Open Photoacoustic Cell Technique, Results for the gas exchange component of the photoacoustic (PA) signal were interpreted considering that the gas uptake component would have a phase angle nearly opposite to that of the oxygen evolution component. By subtracting the thermal component from the total PA signal, we studied the competition between gas uptake and oxygen evolution during the photosynthetic induction. Seedlings presented a net oxygen evolution prior to cuttings, but cuttings reached a higher steady-state photosynthetic activity. The chlorophyll (Chl) a/b ratio and the Chl fluorescence induction characteristic F-v/F-m were significantly higher for cuttings, while there was no difference between samples in stomata density and leaf thickness. Thus the differences in PA signals of seedlings and cuttings are associated to differences between the photosystem 2 antenna systems of these samples.

Spatial variations at different observational scales and the seasonal distributions of stream macroalgae in a Brazilian subtropical region

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Ecological distribution of stream macroalgae in different spatial scales using taxonomic and morphological groups

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

The succession dynamics of a macroalgal community after a flood disturbance in a tropical stream from São Paulo State, southeastern Brazil

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Quantitative distribution of gibberellins and indole-acetic acid in pea (Pisum sativum L.) seedlings

The objective was to determine the distribution in pea seedling of GA (by thin layer chromatography) and IAA (by HPLC). Three samples of 30 7/day-old seedlings were sectioned into: apical meristem + plumular hook; stem elongation zone; stem non-elongation zone; cotyledons; root non-elongation zone; root tip. The material was frozen in liquid N and stored at -80 degrees C. The stem elongation zone, the apical meristem+plumular hook and the root tip had low IAA, whereas the stem non-elongation zone and root non-elongation zone had high IAA content. The stem elongation zone and apical meristem plumular hook had high GA, while root non-elongation zone had the lowest GA content.

Ultrastructure and cytochemistry of the pearl gland in Piper regnellii (Piperaceae)

Pearl glands are scattered throughout the lamina of developing leaves and rarely found on adult leaves of Piper regnellii (Piperaceae). The pearl gland is a bicellular secretory trichome composed of a short broad basal cell and a spatula-like, semiglobular apical cell. Four different stages of the pearl grand were determined during its ontogenesis: origin, pre-secretory, secretory and post-secretory. During the pre-secretory stage, mitochondria, ribosomes, dictyosomes, rough endoplasmic reticulum, and plastids with electron dense inclusions were present in the cytoplasm of the apical cell. During the secretory stage, the most remarkable characteristics of the apical cell are the proliferation of dictyosomes and their vesicles, rough endoplasmic reticulum, and modified plastids. At this stage, electron-dense oil drops occur in the plastids as well as scattered within the cytoplasm, proteins and polysaccharides are seen in the plastids, vesicles, and vacuoles. Only polysaccharides are present in the periplasmic space, wall cavities, and on the surface of the apical cell. The polysaccharides are one of the main components of the mucilagenous exudate that covers the developing leaf structures. The apical cell of the senescing trichomes undergoes a progressive degeneration of its cellular components, the plastids being the first organelles to undergo lysis.

Structural and ultrastructural aspects of ontogenesis and differentiation of resin secretory cavities in Hymenaea stigonocarpa (Fabaceae-Caesalpinioideae) leaves

Cell lysis in the formation of secretory cavities in plants has been questioned by some authors and considered as result of technical artifacts. To describe the formation of secretory resin cavities in Hymenaea stigonocarpa leaves, leaflet samples at different stages of differentiation were collected, fixed, and processed for light and electron microscopy as per usual methods. The initial cells of secretory resin cavities are protodermal and grow towards the mesophyll ground meristem; these cells then divide producing cell groups that are distinguished by the shape and arrangement of cytoplasm, and density. At the initial stages of differentiation of the secretory cavities, some central cells in these groups show dark cytoplasm and condensed nuclear chromatin. Later, there is cell wall loosening, tonoplast and plasmalemma rupture resulting in cell death. These cells, however, maintain organelle integrity until lysis, when the cell wall degrades and the plasmalemma ruptures, releasing protoplast residues, marked characteristics of programmed cell death. The secretory epithelium remains active until complete leaf expansion when the cavity is filled with resin and the secretory activity ceases. There are no wall residues between central cells in adult cavities. Our results demonstrate lysigeny and the importance of ontogenetic studies in determining the origin of secretory cavities.