São Paulo, Brazil
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dos Santos N.O.,University of Sao Paulo | Tavares A.R.,Institute Botanica IBt | Kanashiro S.,Institute Botanica IBt | dos Santos V.R.,Institute Botanica IBt
Ornamental Horticulture | Year: 2016

Costus arabicus L. (Costaceae) is a tropical species native from Brazil. The species has ornamental potential as garden and vase plant, and for flower and stem cutting. The aim of this study was to evaluate the seed germination of C. arabicus under different of light and temperature conditions. Seeds subjected to constant temperatures of 20, 25 and 30 °C under photoperiod of 12 h of light or dark. The parameters analyzed were percentage of germination and germination speed index (GSI). The highest germination percentage (70%) was under temperature of 30 °C, both in light or dark. The GSI showed that the germination rate increases as temperature increases, mainly on 30 °C. C. arabicus seeds germinated in the presence or absence of light, thus was considered neutral photoblastic and germination on light under 30 °C was more efficient for seed germination.

Latansio-Aidar S.R.,Institute Botanica Of Sao Paulo Ibt | de Oliveira A.C.P.,University of Sao Paulo | Da Rocha H.R.,University of Sao Paulo | Aidar M.P.M.,Institute Botanica IBt
Biota Neotropica | Year: 2010

The Cerrado vegetation covers the Brazilian central areas (core area) which include extensive and continuous areas in the central States and some marginal areas in other States, including São Paulo, accounting originally for 21% of Brazilian territory. Nowadays, the remnants are 21,6% of its original coverage. About of 14% of the São Paulo State territory was originally covered with Cerrado vegetation, and today remnants account for less than 1% of the original distribution. Recent studies indicate that the net productivity in the Pé-de-Gigante Cerrado constitutes a small carbon sink, with seasonality playing a major role. The carbon flux studies in terrestrial ecosystems have rarely been accompanied by ecophysiological studies in order to explore the functional relationships among species, ecosystem and the values achieved. Therefore, our objectives were to characterize the vegetation structure in the meteorological and flux tower footprint. The flux tower allows studies related to long term measurements and dynamics of water, solar energy and CO2 fluxes in Cerrado vegetation. Plots (10 × 10 m) were established in 0.2 ha area of Cerrado and all vascular plants with stem perimeter at ground level ≥6 cm (except vines and dead individuals) were sampled. The distribution of diameter classes and vertical structure, as well as the phytosociological parameters were analyzed. We recorded 1,451 individuals, distributed in 85 species belonging to 31 different families. The absolute density and the basal area were 7,255 ind.ha-1 and 7.9 m2.ha-1, respectively. Leguminosae showed the highest number of species (13). The Shannon's Index was 3.27. The distribution of diameter classes showed a curve in inverted "J", most of the individuals being in the initial classes. We concluded that the area must be classified as dense Cerrado, mainly due to Anadenanthera falcata dominance, which occurrence in São Paulo State was reported only in rich soil sites in Cuestas Basaltic regions and also due to major basal area of these individuals, comparing with other Cerrado vegetation sites. A. falcata, Myrcia lingua and Xylopia aromatica showed the highest IVI (Importance value index).

Francisco W.,São Paulo State University | Pivatto M.,São Paulo State University | Pivatto M.,University of Sao Paulo | Danuello A.,São Paulo State University | And 7 more authors.
Journal of Natural Products | Year: 2012

As part of an ongoing research project on Senna and Cassia species, five new pyridine alkaloids, namely, 12′-hydroxy-7′-multijuguinol (1), 12′-hydroxy-8′-multijuguinol (2), methyl multijuguinate (3), 7′-multijuguinol (4), and 8′-multijuguinol (5), were isolated from the leaves of Senna multijuga (syn. Cassiamultijuga). Their structures were elucidated on the basis of spectroscopic data analysis. Mass spectrometry was used for confirmation of the positions of the hydroxy groups in the side-chains of 1, 2, 4, and 5. All compounds exhibited weak in vitro acetylcholinesterase inhibitory activity as compared with the standard compound physostigmine. © 2012 The American Chemical Society and American Society of Pharmacognosy.

Joly C.A.,University of Campinas | Assis M.A.,Claro | Bernacci L.C.,Instituto Agronomico Of Campinas Iac | Tamashiro J.Y.,University of Campinas | And 21 more authors.
Biota Neotropica | Year: 2012

This paper summarizes floristic and phytossociology data of 11, out of 14 plots of 1 ha, allocated along an altitudinal gradient in the Serra do Mar, São Paulo, Brazil. The study was conducted at Serra do Mar State Park and the plots start at the sea level (10 m - plot of Restinga Forest that occurs at Praia da Fazenda, Picinguaba, municipality of Ubatuba) up to 1100 m above sea level (the Montane Ombrophilous Dense occurs alongside the Itamambuca Trail, municipality of São Luis do Paraitinga). The Restinga Forest occurs in Pleistocenic Coastal Plain where the soil is classified as a sandy Quartzipsamment (Quartzenic Neosol), while along the slopes of the Serra do Mar, the Ombrophylus Dense Forest grows on the top of a pre-Cambrian crystalline basement with granitic rocks, where the soil is a sandy-loam Dystrophic Inceptisol (Cambisol/Latosol). In all 14 plots soils are acidic (pH 3 - 4), chemically poor, with high dilution of nutrients and high saturation of aluminum. In the Restinga and at the foot of the slope the climate is Tropical/Subtropical Humid (Af/Cfa), with no dry season, an average annual rainfall over 2,200 mm and an average annual temperature of 22 °C. Towards the top of the Serra do Mar there is a gradual cooling along the slope, but there is no reduction in rainfall, so at 1,100 m above sea level the climate is classified as Humid Subtropical (Cfa/Cfb), with no dry season and an average annual temperature of 17 °C. It is important to remark that, almost daily, from 400 m above sea level up to the top of slopes the mountains are covered by a dense fog. In the 14 plots 21,733 individuals with DBH ≥ 4.8 cm, including trees, palms and ferns, were marked, measured and sampled. The average number of individuals sampled in each plot was 1264 ind.ha-1(± 218 SE 95%). Within the parameters considered trees prevailed (71%in the Montane ODF to 90% in the Restinga Forest), followed by palms (10% in the RF and 25% in the Montane Ombrophilous Dense Forest/ODF) and ferns (0% % in the RF and 4% in the Montane ODF). Regarding these proportions the Exploited Lowlands ODF differs from the others with only 1.8% of palm trees and striking 10% of ferns. The forest canopy is irregular with heights ranging from 7 to 9 m, rarely emergent trees reach 18 m, and due to this irregularity of the canopy the amount of light that gets through sets conditions for the development of hundreds of epiphytic species. Aside from Montana ODF, where the number of dead trees was more than 5% of individuals sampled, in the other phytophysiognomies this value was below 2.5%. In the 11 plots where the floristic study was conducted we found 562 species in 195 genera and 68 families. Only seven species - Euterpe edulis Mart. (Arecaceae), Calyptranthes lucida Mart. ex DC. and Marlierea tomentosa Cambess (both Myrtaceae), Guapira opposita (Vell.) Reitz (Nyctaginaceae), Cupania oblongifolia Mart. (Sapindaceae), Cecropia glaziovii Snethl. and Coussapoa microcarpa (Schott) Rizzini (both Urticaceae) - occurred from Restinga to Montane ODF, while 12 other species did not occur only in the Restinga Forest. Families with the greatest number of species are Myrtaceae (133 spp), Fabaceae (47 spp), Rubiaceae (49) and Lauraceae (49) throughout the gradient and Monimiaceae (21) specifically in portions Montane ODF. Only in the F plot, where logging has occurred between 1950 and 1985, the abundance of palm trees has been replaced by Cyatheaceae. The study shows a peak of diversity and richness, Shannon-Weiner index (H') ranging from 3.96 to 4.48 nats.ind-1, in the intermediate altitudes (300 to 400 m) along the slope. Several explanations for thishytophysiognomies of the Atlantic ODF due to climate fluctuations during the Pleistocene. The results presented in this paper d result are raised here, including the fact that these elevations are within the limits expansions and retractions of the different pemonstrate the extraordinary richness of tree species of the Atlantic Rainforest from the northeastern coast of the State of Sao Paulo, reinforcing the importance of its conservation throughout the altitudinal gradient. The richness of this forest justifies a long term commitment to study its dynamics and functioning through permanent plots, and monitor the impacts of climate change in this vegetation.

Suguiyama V.F.,Institute Botanica IBt | Suguiyama V.F.,Federal University of ABC | Sanches R.F.E.,Institute Botanica IBt | Meirelles S.T.,University of Sao Paulo | And 3 more authors.
South African Journal of Botany | Year: 2016

Resurrection plants are able to tolerate the extreme desiccation of their vegetative tissues and after the increase of water availability recover their full metabolic capacity. This capacity that depends on the regulatory mechanisms that allow metabolism occurs under low water potential until the anabiosis state. The responses to the desiccation process in Barbacenia purpurea (Velloziaceae), a resurrection plant commonly found in rock outcrops in Rio de Janeiro, Brazil, start when leaf water relative content decreases below 70%. In this work, we studied the influence of total water withholding on physiological and metabolic parameters during desiccation of B. purpurea under winter and summer conditions. Throughout the desiccation process of B. purpurea, morphological alterations such as subtle leaf curling and osmotic adjustment were observed in both winter and summer seasons. Increased uronic acid content in the leaf cell walls also occurred in response to water suppression in both seasons. Despite some fluctuations, no significant differences in antioxidant activity during dehydration/rehydration were observed. Our findings indicate that the mechanisms implicated in desiccation tolerance in this species are governed by leaf water status and that the intensity of physiological and metabolic responses is modulated by seasonality due to the amplitude of the environmental changes in each season. © 2016 South African Association of Botanists.

Marques S.S.,Fundacao Ceciliano Abel de Almeida FCAA | Oliveira J.T.S.,Federal University of Espirito Santo | Paes J.B.,Federal University of Espirito Santo | Alves E.S.,Institute Botanica IBT | And 2 more authors.
Revista Arvore | Year: 2012

Among physical properties of the wood, specific gravity and shrinkage are the most important characteristics to evaluate the wood quality and indication to several uses. Apparent specific gravity or density is an important physical characteristic that is related with shrinkage and others characteristics asthe mechanical and anatomical properties of the wood. Shrinkage is also an important characteristic because it determines as wood dimensional stability which is an important property for several uses in which wood should not present excessive contraction when being used. Thus, the objective of this study was to compare the specific gravity and shrinkage of Pernambuco wood (Caesalpinia echinata) from natural areas and reforestation at the ages of 10, 15, 20, 25 and 30 years. This study followed the Brazilian Method 26/1940 of Brazilian Associations of Technical Standard. The results indicate that there was variation in the apparent specific gravity and dry density atthe different ages with the highest value found for the wood at 30thirty years of age which was similar to the ones found for samples of native wood. The wood shrinkage also presented variation in function of the age but it did do not show differences in relation to native wood.

Santana L.M.,State University of Santa Cruz | Santana L.M.,Institute Botanica IBt | Moraes M.E.B.,State University of Santa Cruz | Silva D.M.L.,State University of Santa Cruz | Ferragut C.,Institute Botanica IBt
Brazilian Journal of Biology | Year: 2016

This study aims to evaluate the environmental factors determining of the changes in phytoplankton structure in spatial (upper, middle and lower course) and seasonal (dry and rainy period) scales in a eutrophic river (Almada River, northeastern Brazil). In the study period, total accumulated rainfall was below of the historic average, resulting in flow reduction, mainly in rainy period. High orthophosphate concentration was found at the sampling sites. Phytoplankton chlorophyll a increased from upstream to downstream. Geitlerinema splendidum (S1) and Chlamydomonas sp. (X2) were the most abundant species in the upper course and several species of diatoms (D), Euglenophyceae (W1, W2) and Chlorophyceae (X1) in the middle and lower course. The functional groups were found to be characteristic of lotic ecosystem, shallow, with low light availability, rich in organic matter and eutrophic environments. We conclude that phytoplankton community structure was sensitive to change of the river flow and nutrient availability in spatial and seasonal scale in a tropical river. © 2016, Instituto Internacional de Ecologia. All rights reserved.

Malone C.F.S.,Institute Botanica IBt | Santos K.R.S.,Institute Botanica IBt | Sant'Anna C.L.,Institute Botanica IBt
Oecologia Australis | Year: 2012

The alkaline lakes, known as "salinas", in Pantanal are typical examples of extreme environments due to their high pH (>9) values. The present study showed the particularities of the microflora in these alkaline lakes that is composed of alkaliphic species such as Anabaenopsis elenkinii, Anomoeoneis sphaerophora var. sphaerophora and Nitzschia intermedia. Besides, it was detected that natural or anthropogenic disturbances that allowed freshwater from adjacent lakes go into the "salinas", totally modified the typical flora of these systems. Thus, our study indicates that the natural condition of isolation of the alkaline lakes should be preserved and that the composition of its microflora is a very important tool to evaluate the changes in these systems.

Pelissari G.,Institute Botanica IBt | Romaniuc Neto S.,Institute Botanica IBt
Rodriguesia | Year: 2013

Serra da Mantiqueira is a mountain chain located in southeastern Brazil. It is located between the Atlantic Forest and Cerrado biomes, extending to four states in the region, with its major portion in the state of Minas Gerais and the minor one within Espírito Santo State, in Serra do Caparaó. Ficus L. is the largest genus of the family Moraceae, with approximately 800 species distributed in tropical regions, including shrubs, trees, hemiepiphytes and vines. The most striking features are the syconium inflorescence and pollination by wasps. For this study we examined materials deposited in scientific collections, as well as field trips, and observations of populations in nature. We found 25 species of Ficus, being 17 native and eight exotic. Descriptions, comments on phenology and geographic distribution, conservation, taxonomic comments and illustrations are presented. Native species are described here, of which six are considered endangered due to habitat fragmentation and anthropogenic interference.

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