Disposition of two names in Almeidea (Rutaceae)

(Disposition of two names in Almeidea (Rutaceae)). Examination of type specimens at the P herbarium showed that Almeidea longifolia A. St.-Hil. (Rutaceae) is an illegitimate substitute name for A. affinis A. St.-Hil. The latter name is proposed here as a heterotypic synonym of A. rubra A. St.-Hil.

A new dwarf shrubby species of Baccharis subg. Baccharis (Asteraceae, Astereae) from southeastern Brazil

Baccharis dichotoma, a new dwarf shrubby species, with small leaves and few heads, of high-altitude grasslands from southeastern Brazil, is described, illustrated, and assigned to subgenus Baccharis.

Lapanthus (Bromeliaceae, Bromelioideae): A New Genus from the Southern Espinhaco Range, Brazil

In this paper we describe a new genus of Bromehaceae, Lapanthus, restricted to the southern portion of the Espinhaco Range, Minas Germs State, in southeastern Brazil Two new combinations to accommodate species previously described in the genera Orthophytum and cryptanthus and one new synonym are proposed Lapanthus has morphological affinities with both Cryptanthus and Orthophytum but nevertheless differs by the combination of margins of the petals ciliate, presence of lanceolate petal appendages and free stamens, and also by molecular data Cryptanthus and Orthophytum have petals entire along the margins, and the filaments of the most internal whorl are adnate to the petals Lapanthus stands out by having a pair of lanceolate petal appendages, which are almost completely adnate to the petals In Orthophytum, however, appendages are cupuhform or sacciform and they are totally absent in the genus Cryptanthus Lapanthus and Orthophytum present meiotic and mitotic chromosome numbers equal to n=25 and 2n=50, 100 and 150 respectively, while Cryptanthus presents meiotic and mitotic chromosome numbers n=17 and 2n=34, 36, 54 respectively, and this difference is considered to be an autapomorphic feature of Cryptanthus Descriptions of the genus and species, identification keys, illustrations, photographs of living specimens, and taxonomic comments are provided

Polyamines, IAA and ABA during germination in two recalcitrant seeds: Araucaria angustifolia (Gymnosperm) and Ocotea odorifera (Angiosperm)

Background and Aims Plant growth regulators play an important role in seed germination. However, much of the current knowledge about their function during seed germination was obtained using orthodox seeds as model systems, and there is a paucity of information about the role of plant growth regulators during germination of recalcitrant seeds. In the present work, two endangered woody species with recalcitrant seeds, Araucaria angustifolia (Gymnosperm) and Ocotea odorifera (Angiosperm), native to the Atlantic Rain Forest, Brazil, were used to study the mobilization of polyamines (PAs), indole-acetic acid (IAA) and abscisic acid (ABA) during seed germination. Methods Data were sampled from embryos of O. odorifera and embryos and megagametophytes of A. angustifolia throughout the germination process. Biochemical analyses were carried out in HPLC. Key Results During seed germination, an increase in the (Spd + Spm) : Put ratio was recorded in embryos in both species. An increase in IAA and PA levels was also observed during seed germination in both embryos, while ABA levels showed a decrease in O. odorifera and an increase in A. angustifolia embryos throughout the period studied. Conclusions The (Spd + Spm) : Put ratio could be used as a marker for germination completion. The increase in IAA levels, prior to germination, could be associated with variations in PA content. The ABA mobilization observed in the embryos could represent a greater resistance to this hormone in recalcitrant seeds, in comparison to orthodox seeds, opening a new perspective for studies on the effects of this regulator in recalcitrant seeds. The gymnosperm seed, though without a connective tissue between megagametophyte and embryo, seems to be able to maintain communication between the tissues, based on the likely transport of plant growth regulators.

Nitrosyl ethylenediaminetetraacetate ruthenium(II) complex promotes cellular growth and could be used as nitric oxide donor in plants

Over recent years nitric oxide (NO) not only has appeared as an important endogenous signaling molecule in plants and as a mediator in many developmental and physiological processes, but has also received recognition as a plant hormone. The impressive recent achievements in elucidating the role of NO in plants have come about by the application of NO donors. The aim herein was to study the effects of the different NO donors, sodium nitroprusside (SNP) and the nitrosyl ethylenediaminetetraacetate ruthenium(II) ([Ru(NO)(Hedta)]) complex on cellular growth in embryogenic suspension cultures of Araucaria angustifolia. Appraisal of our data revealed that [Ru(NO)(Hedta)] stimulated about 60% of cellular growth in embryogenic suspension cultures of A. angustifolia, with results similar to those observed with the SNP donor. Nevertheless, application of the NO scavenger PTIO (2-phenyl-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide) inhibited this cellular growth in both. Cellular growth was correlated with an increase in endogenous NO levels after 21 days of culture, especially in treatments with NO donors. Our results demonstrated that the [Ru(NO)Hedta] complex could possibly be used as a NO donor in plants. (C) 2010 Elsevier Ireland Ltd. All rights reserved.

A new species of Croton section Cleodora (Euphorbiaceae s.s.) from Minas Gerais, Brazil

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Araucaria forest dynamics in relation to fire frequency in southern Brazil based on fossil and modern pollen dataf

To elucidate the relationship between forest dynamics and fire frequency pollen percentages and charcoal amounts from a 120 cm long peat core and from samples of modern pollen rain were collected along a transect. The study site in southern Brazil is characterized by a species-rich mosaic of grassland-Araucaria forest. It is of crucial importance for management strategies for conservation to understand the development and maintenance of these vegetation mosaics including their sharp forest-grassland boundaries. During the late Holocene, considerable changes occurred in the area. From Anno Domini (AD) 1360 to 1410, the area was dominated by Campos (grassland) vegetation and fire was very common. From AD 1410 to 1500, Araucaria forest expanded and fire was less frequent. From AD 1500 to 1580, Campos grassland spread and the Araucaria forest ceased its development, apparently due to the increase of fire. From AD 1580 to 1935, after a decrease in fire frequency, Araucaria forest expanded again. From AD 1935 to the present, the Araucaria forest expanded while the Campos area decreased. Fire was very rare in this period. The results indicate a strong interaction of forest expansion, forming a mosaic of Campos and Araucaria forest, and the frequency of fire during the past 600 years. A possible collapse of the indigenous population following the post-Colombian colonization in southern Brazil after about AD 1550 may have caused a great reduction of fire frequency. The introduction of cattle (probably after AD 1780) and the resulting decrease of fire frequency might be the reason for forest expansion. Fire is probably the most important factor controlling the dynamics of the forest-grassland mosaics and the formation of sharp borders between these two vegetation types. (C) 2010 Elsevier B.V. All rights reserved.

Genomic Analysis of Wild Tomato Introgressions Determining Metabolism- and Yield-Associated Traits

With the aim of determining the genetic basis of metabolic regulation in tomato fruit, we constructed a detailed physical map of genomic regions spanning previously described metabolic quantitative trait loci of a Solanum pennellii introgression line population. Two genomic libraries from S. pennellii were screened with 104 colocated markers from five selected genomic regions, and a total of 614 bacterial artificial chromosome (BAC)/cosmids were identified as seed clones. Integration of sequence data with the genetic and physical maps of Solanum lycopersicum facilitated the anchoring of 374 of these BAC/cosmid clones. The analysis of this information resulted in a genome-wide map of a nondomesticated plant species and covers 10% of the physical distance of the selected regions corresponding to approximately 1% of the wild tomato genome. Comparative analyses revealed that S. pennellii and domesticated tomato genomes can be considered as largely colinear. A total of 1,238,705 bp from both BAC/cosmid ends and nine large insert clones were sequenced, annotated, and functionally categorized. The sequence data allowed the evaluation of the level of polymorphism between the wild and cultivated tomato species. An exhaustive microsynteny analysis allowed us to estimate the divergence date of S. pennellii and S. lycopersicum at 2.7 million years ago. The combined results serve as a reference for comparative studies both at the macrosyntenic and microsyntenic levels. They also provide a valuable tool for fine-mapping of quantitative trait loci in tomato. Furthermore, they will contribute to a deeper understanding of the regulatory factors underpinning metabolism and hence defining crop chemical composition.

The gynoecium of male Anchietea pyrifolia (Violaceae): Preserved structure with a new function

Structure of inflorescences and flowers and flowering behaviour are reported for the woody liana Anchietea pyrifolia (Violaceae) from Brazil. The specimen studied is grown for some decades now in the greenhouses of Halle Botanical Garden and turned out unisexually male, which adds a further example of dioecism to the family Violaceae, in which this type of sex distribution is rarely encountered. The flowers are exceptional also for the strongly asymmetric anterior petal, which represents a rare case of a species with enantiomorphic flowers pollinated by Lepidoptera. They have a fully developed gynoecium with a complicated architecture comparable to the pistil of bisexual Violaceae flowers, though without ovules. The style head is capable to release viscose liquid on tactile stimulation or pressure, which is known to act as pollen-gathering mechanism in bisexual Violaceae species with usually dry pollen and buzz-pollination. This function has switched in male A. pyrifolia to a mechanism for efficient pollen release mediated by insect pollinators from its short-lived flowers. (C) 2009 Elsevier GmbH. All rights reserved.

Specific leaf areas of the tank bromeliad Guzmania monostachia perform distinct functions in response to water shortage

Leaves comprise most of the vegetative body of tank bromeliads and are usually subjected to strong longitudinal gradients. For instance, while the leaf base is in contact with the water accumulated in the tank, the more light-exposed middle and upper leaf sections have no direct access to this water reservoir. Therefore, the present study attempted to investigate whether different leaf portions of Guzmania monostachia, a tank-forming C(3)-CAM bromeliad, play distinct physiological roles in response to water shortage, which is a major abiotic constraint in the epiphytic habitat. Internal and external morphological features, relative water content, pigment composition and the degree of CAM expression were evaluated in basal, middle and apical leaf portions in order to allow the establishment of correlations between the structure and the functional importance of each leaf region. Results indicated that besides marked structural differences, a high level of functional specialization is also present along the leaves of this bromeliad. When the tank water was depleted, the abundant hydrenchyma of basal leaf portions was the main reservoir for maintaining a stable water status in the photosynthetic tissues of the apical region. In contrast, the CAM pathway was intensified specifically in the upper leaf section, which is in agreement with the presence of features more suitable for the occurrence of photosynthesis at this portion. Gas exchange data indicated that internal recycling of respiratory CO(2) accounted for virtually all nighttime acid accumulation, characterizing a typical CAM-idling pathway in the drought-exposed plants. Altogether, these data reveal a remarkable physiological complexity along the leaves of G. monostachia, which might be a key adaptation to the intermittent water supply of the epiphytic niche. (C) 2009 Elsevier GmbH. All rights reserved.

A New Species of Rhipsalis (Cactaceae) from Brazil

A new species of Rhipsalis (Cactaceae) from Rio de Janeiro State, in southwestern Brazil, is described and illustrated. The new Rhipsalis aurea is circumscribed in the subgenus Eryhtrorhipsalis and is morphologically most similar to R. pulchra Loefgr., but is distinct by the smaller, suberect habit, smaller secondary stem segments of determinated growth, golden yellow flowers, depressed-globose fruit, and epidermis and pollen grain features. Following the IUCN criteria this new species is vulnerable due to its restricted area of occurrence and reduction of the quality of habitat observed in the present and projected for the future. A taxonomic key to the subgenus Erythrorhipsalis is included.

First evidence of insect attraction by a Southern Hemisphere Splachnaceae: The case of Tayloria dubyi Broth. in the Reserve Biosphere Cape Horn, Chile

The moss Tayloria dubyi (Splachnaceae) is endemic to the subantarctic Magallanes ecoregion where it grows exclusively on bird dung and perhaps only on feces of the goose Chloephaga picta, a unique habitat among Splachnaceae. Some species of Splachnaceae from the Northern Hemisphere are known to recruit coprophilous flies as a vector to disperse their spores by releasing intense odors mimicking fresh clung or decaying corpses. The flies land on the capsule, and may get in contact with the protruding mass of spores that stick to the insect body. The dispersal strategy relies on the spores falling off when the insect reaches fresh droppings or carrion. Germination is thought to be rapid and a new population is quickly established over the entire substrate. The objectives of this investigation were to determine whether the coprophilous T. dubyi attracts flies and to assess the taxonomic diversity of the flies visiting this moss. For this, fly traps were set up above mature sporophyte bearing populations in two peatlands on Navarino Island. We captured 64 flies belonging to the Muscidae (Palpibracus chilensis), Tachinidae (Dasyuromyia sp) and Sarcophagidae (not identified to species) above sporophytes of T. dubyi, whereas no flies were captured in control traps set up above Sphagnum mats nearby.

Antineoplasic activity of Copaifera multijuga oil and fractions against ascitic and solid Ehrlich tumor

The aim of this study was to investigate the effect of chronic treatment with C. multijuga oil on Ehrlich tumor evolution. C multijuga was fractionated in a KOH impregnated silica gel column chromatography to give three distinct fractions, i.e., hexanic, chloroformic, and methanolic, mainly composed by hydrocarbon sesquiterpenes, oxygenated sesquiterpenes and acidic diterpenes, respectively. Results demonstrated that the C multijuga oil, the hexanic, and chloroformic fractions did not develop toxic effects. The oil, hexanic and chloroformic fractions (doses varying between 100 and 200 mg/kg) showed antineoplasic properties against Ehrlich ascitic tumor (EAT) and solid tumor during 10 consecutive days of treatment inhibiting ascitic tumor cell number, reverting medulla and blood cell counts to values similar to control group, and inhibiting the increase on several inflammatory mediators (total protein, PGE(2), nitric oxide, and TNF) on ascitic fluid. The treatment also inhibited the increase in paw volume on tumor-inoculated mice. In conclusion, C. multijugo as well as its fractions demonstrated antineoplasic effect even after oral administration confirming its use by traditional medicine. (C) 2008 Elsevier Ireland Ltd. All rights reserved.

The effect of sixteen medicinal plants used in the Brazilian pharmacopoeia on the expression and activity of glutathione S-transferase in hepatocytes and leukemia cells

Glutathione S-transferase (GST) is a family of enzymes involved in the detoxification of electrophilic compounds. Different classes of GST are expressed in various organs, such as liver, lungs, stomach and others. Expression of GST can be modulated by diet components and plant-derived compounds. The importance of controlling GST expression is twofold: increasing levels of GST are beneficial to prevent deleterious effects of toxic and carcinogenic compounds, while inhibition of GST in tumor cells may help overcoming tumor resistance to chemotherapy. A screening of 16 plants used in the Brazilian pharmacopoeia tested their effects on GST expression in hepatocytes and Jurkat (leukemia) T-cells. The methanol extracts of five plants inhibited GST expression in hepatocytes. Three plants significantly inhibited and four others induced GST expression in Jurkat cells. Among these, the extracts of Bauhinia forficata Link. (Leguminosae) and Cecropia pachystachya Trec. (Urticaceae) inhibited GST expression at relatively low concentrations. With the exception of B. forficata, all plants were cytotoxic when administered to Jurkat cells at high doses (1 mg/mL) and some extracts were considerably cytotoxic even at lower concentrations.

Morphometric analysis and taxonomic revision of the Vriesea paraibica complex (Bromeliaceae)

The species related to Vriesea paraibica (Bromeliaceae, Tillandsioideae) have controversial taxonomic limits. For several decades, this group has been identified in herbarium collections as V. x morreniana, an artificial hybrid that does not grow in natural habitats. The aim of this study was to assess the morphological variation in the V. paraibica complex through morphometric analyses of natural populations. Two sets of analyses were performed: the first involved six natural populations (G1) and the second was carried out on taxa that emerged from the first analysis, but using material from herbarium collections (G2). Univariate ANOVA was used, as well as discriminant analysis of 16 morphometric variables in G1 and 18 in G2. The results of the analyses of the two groups were similar and led to the selection of diagnostic traits of four species. Lengths of the lower and median floral bracts were significant for the separation of red and yellow floral bracts. Vriesea paraibica and V. interrogatoria have red bracts; these two species are differentiated by the widths of the lower and median portions of the inflorescence and by scape length. These structures are larger in the former and smaller in the latter. Of the species with yellow floral bracts, V. eltoniana is distinguished by longer leaf blades and scapes and V. flava is characterized by its shorter sepal lengths. (C) 2009 The Linnean Society of London, Botanical Journal of the Linnean Society, 2009, 159, 163-181.