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Medina B.M.O.,Fundacao Brasileira para o Desenvolvimento Sustentavel | Ribeiro K.T.,Instituto Chico Mendes Of Conservacao Da Biodiversidade Icmbio | Aximoff I.A.,Institute Pesquisa Do Jardim Botanico Do Rio Of Janeiro | Scarano F.R.,Fundacao Brasileira para o Desenvolvimento Sustentavel | Scarano F.R.,Federal University of Rio de Janeiro
Oecologia Australis | Year: 2016

Stevia camporum (Asteraceae) is a threatened and endemic geophyte of the rocky outcrop vegetation in the high altitude grasslands on the top of the Itatiaia massif. This is a locally abundant plant, which establishes itself preferentially on vegetation mats dominated by pioneer species such as mosses (Campylopus pilifer) and by the vascular endemic plants Fernseea itatiaiae and Barbacenia gounelleana. With a very distinctive morphology, these nurse plants may differently influence the dynamics of S. camporum. These relations were previously studied for two years when a 3-day unnatural fire burned the grassy vegetation around the rocky outcrops, thereby affecting indirectly the vegetation mats (islands) growing at the exposed rocky surfaces, through ash emissions and changes on the availability of nutrients. We described pre-fire (1999-2001) and post-fire (2002-2003) population demography and growth of S. camporum under the hypothesis that Stevia demography would change due to effects of fire, such as nutrient income and, further, that responses would vary according to the dominant pioneer species of each vegetation mat. Forty-three islands containing S. camporum (total area of 30.08m2) were monitored. Despite considerable variation in rainfall between years, population structure and dynamics of S. camporum were very similar in the two pre-fire growing seasons. A massive increase in the frequency of branches in the first size class followed fire, but with nearly no changes in the other classes with a thinning process being observed. The height, number of nodes and number of fruits of Stevia camporum’s ramets showed significant differences when comparing the values for periods before and after the fire. Stevia’s demography on Fernseea (Bromeliaceae) mats was significantly different in relation to the other mat species, after fire. In Itatiaia, indirect effects of smoke produced by fire episodes seem to trigger rapid responses on rupicolous communities followed by rapid return to previous conditions, particularly in secondary species. Prolonged effects on more often disturbed communities remain to be seen, and might be relevant to community structure of high altitude outcrop vegetation. © 2016, Universidade Federal do Rio de Janeiro (UFRJ). All rights reserved.

Resende C.F.,Federal University of Juiz de fora | Braga V.F.,Federal University of Juiz de fora | Pereira P.F.,Federal University of Juiz de fora | Silva C.J.,Federal University of Juiz de fora | And 5 more authors.
Brazilian Journal of Biology | Year: 2016

This study aimed to evaluate the variation in the levels of proline, oxidative metabolism and photosynthetic pigments in plants of Pitcairnia encholirioides grown in vitro under different conditions and after acclimatization. The analyses were performed after 150 days of in vitro cultivation in MS media supplemented with 10 μM GA3 or 0.2 μM NAA, sucrose at 15 or 30 g L-1, in test tubes which allowed gas exchange or in a hermetically sealed system, and 180 days after acclimatization. The in vitro maintenance in hermetically sealed flasks, with GA3 and 15 g L-1 sucrose had adverse metabolic effects, which was demonstrated by the lower proline and photosynthetic pigments accumulation and by the increase in antioxidant enzymes activities. After acclimatization, differences for proline and photosynthetic pigments were no longer found and the enzymatic activities ranged unevenly. The results suggest that the in vitro cultivation in media with 0.2 μM NAA and 30 g L-1 sucrose, in test tubes capped with closures which allowed gas exchange, is more suitable for micropropagation of P. encholirioides, providing a prolonged maintenance of in vitro cultures and plantlets with superior quality for ex vitro development. © 2016, Instituto Internacional de Ecologia. All rights reserved.

Pederneiras L.C.,Institute Botanica | Romaniuc-Neto S.,Institute Botanica | Mansano V.D.F.,Institute Pesquisa Do Jardim Botanico Do Rio Of Janeiro
Systematic Botany | Year: 2015

Ficus subg. Pharmacosycea sect. Pharmacosycea has never been comprehensively sampled in previous phylogenetic analyses of Ficus. The published phylogenies have focused mostly on the study of the whole genus, with a sampling of only a few taxa fromthis group. Our study represents the first molecular phylogenetic analysis focusing on this section, including 27 terminals representing 20 of its 35 species and 31 other species of Ficus. The analyses of three nuclear DNA sequences (ITS, G3pdh, and ETS) add considerably to our knowledge of the phylogenetic relationships within this peculiar section, and lead to proposed taxonomicmodifications. The monophyly of this section, aswell as its position as sister to the rest of Ficus, is supported by our maximum likelihood and Bayesian analyses. As previously circumscribed, F. subsect. Bergianae is monophyletic, and F. subsect. Petenenses is paraphyletic. A third well-supported clade is sister to the Petenenses-Bergianae clade, characterized by an hemiepiphyc life form. We describe this new subsection here as Ficus subsect. Carautaea. © Copyright 2015 by the American Society of Plant Taxonomists.

Pederneiras L.C.,Institute Botanica | Pederneiras L.C.,Institute Pesquisa Do Jardim Botanico Do Rio Of Janeiro | Neto S.R.,Institute Botanica
Systematic Botany | Year: 2015

A new species of Ficus sect. Pharmacosycea, occurring in the Venezuelan Amazon, is here described and illustrated as Ficus crateriformis Pederneiras and Romaniuc. The new species shows similarities with F. carvajalii, F. macrosyce and F. pulchella although it is characterized mainly by the crateriform apex of the syconium, and leaf blades 12-19 cm long with 19-23 pairs of lateral veins. Discussions on taxonomy and geographic distribution are provided, as well as an identification key to the species in Venezuela. © Copyright 2015 by the American Society of Plant Taxonomists.

The occurrence of Alouatta guariba clamitans in the Itatiaia National Park (PNI) are considered rare. For over 70 years an epizootic outbreak of yellow fever almost caused the local extinction of this species and since then only one record by direct observation was obtained. In this study, records were obtained by direct observation of a group of four adults, one male and three females, and an infant in forest environment (ca. 1200m). One of the females presented anomaly in the coloration, characterized as leucism. A record of solitary adult male was held in high altitude grasslands (2450m). It is possible that the fault is related to the low density of the species, similar to that reported in other studies. The case record in high altitude, which can be considered the highest for primates in the country, suggests expanding the occurrence of possibilities and use area for the species. The monitoring of this species is to be continuously executed, including higher areas, in order to obtain accurate estimates of density. The performance of activities for its conservation, such as the translocation of individuals from surrounding areas to the PNI should be assessed, to avoid their possible local extinction. © 2016, Universidade Federal do Rio de Janeiro (UFRJ). All rights reserved.

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