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Broad patterns across wild plant species show that leaf composition and morphology vary predictably among habitats, richer habitats favoring resource-acquisition strategies and poorer habitats favoring resource-conservation strate...
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Broad patterns across wild plant species show that leaf composition and morphology vary predictably among habitats, richer habitats favoring resource-acquisition strategies and poorer habitats favoring resource-conservation strategies. Domestication is often accompanied by a shift to richer habitats, and might thus be expected to lead to a shift in leaf composition and morphology and hence in photosynthetic parameters. We compared leaf photosynthetic parameters in domesticated cassava (Manihot esculenta) and a close wild relative, using greenhouse-grown plants. In domesticated cassava, CO exchange rate expressed per unit mass and specific leaf area (SLA, mpo/kg dry mass) were greater than in the wild relative, whereas leaf dry matter content (LDMC, dry mass/fresh mass) was lower in the domesticate. These results suggest that SLA and net photosynthetic rates may both have increased in the evolution of cassava under domestication, enabling more rapid growth in relatively resource-rich and protected agricultural habitats. Previous comparisons of photosynthetic rates in domesticated plants and wild relatives have usually considered only leaf area-based measures. Here, we discuss the interest of using mass-based rates to study the evolution of ecological strategies under domestication.
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Genetic variation was investigated using AFLP markers in 12 populations of Anthurium sinuatum and A. pentaphyllum var. pentaphyllum (Araceae) in north-east Brazil, Amazonia and the Brazilian Atlantic forest. Two unique genetic pat...
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Genetic variation was investigated using AFLP markers in 12 populations of Anthurium sinuatum and A. pentaphyllum var. pentaphyllum (Araceae) in north-east Brazil, Amazonia and the Brazilian Atlantic forest. Two unique genetic patterns characterizedthe populations of A. sinuatum as a group, but no correlation between genetic and geographical interpopulation distance was found; the Amazonian population was not separated from that in CearcL. The isolated CearcL brejo populations of A. sinuatum weregenetically distinct, but genetic diversity levels were similar to populations elsewhere, with no evidence of genetic erosion. Anthurium pentaphyllum populations were significantly different from each other; Bayesian genetic structural analysis found nocommon genetic pattern, but revealed genetic clusters unique to subgroups and individual populations in the Atlantic forest and French Guiana. Anthurium pentaphyllum and A. sinuatum can be distinguished genetically, but individuals of both species formedintermediate genetic clusters that blurred their distinction. We suggest that genetic mixing of A. sinuatum and A. pentaphyllum has occurred in north-east Brazil, possibly connected with cycles of humid forest expansion. The weak genetic structure in A.sinuatum is consistent with the natural fragmentation of continuous forest areas, possibly during the Holocene. This study highlights the scientific importance of the highly threatened brejo forests for tropical American biogeography.
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1. As trees in a given cohort progress through ontogeny, many individuals die. This risk of mortality is unevenly distributed across species because of many processes such as habitat filtering, interspecific competition and negati...
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1. As trees in a given cohort progress through ontogeny, many individuals die. This risk of mortality is unevenly distributed across species because of many processes such as habitat filtering, interspecific competition and negative density dependence. Here, we predict and test the patterns that such ecological processes should inscribe on both species and phylogenetic diversity as plants recruit from saplings to the canopy. 2. We compared species and phylogenetic diversity of sapling and tree communities at two sites in French Guiana. We surveyed 2084 adult trees in four 1-ha tree plots and 943 saplings in sixteen 16-mpo subplots nested within the tree plots. Species diversity was measured using Fisher's alpha (species richness) and Simpson's index (species evenness). Phylogenetic diversity was measured using Faith's phylogenetic diversity (phylogenetic richness) and Rao's quadratic entropy index (phylogenetic evenness). The phylogenetic diversity indices were inferred using four phylogenetic hypotheses: two based on rbcLa plastid DNA sequences obtained from the inventoried individuals with different branch lengths, a global phylogeny available from the Angiosperm Phylogeny Group, and a combination of both. 3. Taxonomic identification of the saplings was performed by combining morphological and DNA barcoding techniques using three plant DNA barcodes (psbA-trnH, rpoC1 and rbcLa). DNA barcoding enabled us to increase species assignment and to assign unidentified saplings to molecular operational taxonomic units. 4. Species richness was similar between saplings and trees, but in about half of our comparisons, species evenness was higher in trees than in saplings. This suggests that negative density dependence plays an important role during the sapling-to-tree transition. 5. Phylogenetic richness increased between saplings and trees in about half of the comparisons. Phylogenetic evenness increased significantly between saplings and trees in a few cases (4 out of 16) and only with the most resolved phylogeny. These results suggest that negative density dependence operates largely independently of the phylogenetic structure of communities. 6. Synthesis. By contrasting species richness and evenness across size classes, we suggest that negative density dependence drives shifts in composition during the sapling-to-tree transition. In addition, we found little evidence for a change in phylogenetic diversity across age classes, suggesting that the observed patterns are not phylogenetically constrained.
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Phylogeographic trends in Batrachospermum macrosporum Mont. were investigated using the mitochondrial intergenic spacer between the cytochrome oxidase subunit 2 and 3 genes (cox2-3). A total of 11 stream segments were sampled with...
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Phylogeographic trends in Batrachospermum macrosporum Mont. were investigated using the mitochondrial intergenic spacer between the cytochrome oxidase subunit 2 and 3 genes (cox2-3). A total of 11 stream segments were sampled with seven in the coastal plain of North America and four in tropical areas of South America. Fifteen thalli were sampled from seven streams, 14 thalli from two streams, and eight thalli from two streams. There were 16 haplotypes detected using 149 individuals. Of the eight haplotypes from locations in North America, all were 334 base pairs (bp) in length, and of those from South America, five were 344 bp, and three were 348 bp. Two individual networks were produced: one for the haplotypes from North America and another for those from South America, and these could not be joined due to the large number of base pair differences. This split between haplotypes from North and South America was confirmed with sequence data of the rbcL gene. There was very little genetic variation among the haplotypes from the North American locations, leading us to hypothesize that these are fairly recent colonization events along the coastal plain. In contrast, there was high variation among haplotypes from South America, and it would appear that the Amazon serves as a center of diversity. We detected considerable variation in haplotypes among streams, but frequently, a single haplotype in an individual stream segment, which is consistent with data from previous studies of other batrachospermalean taxa, may suggest a single colonization event per stream.
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The authors give a list of 40 species of mosses collected by M. Kuc in the coastal belt of French Guiana. In this paper, the authors provide a list of the mosses collected by M. Kuc in the coastal belt of French Guiana during Sept...
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The authors give a list of 40 species of mosses collected by M. Kuc in the coastal belt of French Guiana. In this paper, the authors provide a list of the mosses collected by M. Kuc in the coastal belt of French Guiana during September 1982. There were three collection localities (Fig. 1).
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A workshop on epidemiology and management of snakebites in French Guiana was performed at Cayenne, French Guiana from September 15 to September 16, 2017, under the auspices of the French Regional Health Agency (ARS) and the Pan Am...
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A workshop on epidemiology and management of snakebites in French Guiana was performed at Cayenne, French Guiana from September 15 to September 16, 2017, under the auspices of the French Regional Health Agency (ARS) and the Pan American Health Organization (PAHO). The activity was attended by experts from France (Angers, Martinique, French Guiana, Guadeloupe, and Paris), Costa Rica, Brazil, Saint Lucia, and Surinam. The epidemiology, clinical manifestations, clinical grading and the management of snakebite in French Guiana were discussed. The conclusions of this symposium illustrated the urgent need to ensure accessibility of effective and safe polyvalent viperid antivenom in French Guiana. Finally, the results of this symposium have forged ties based on mutual goals and objectives. (C) 2018 Elsevier Ltd. All rights reserved.
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The commensal small non-volant mammals found in traditional houses of Wayampi Amerindians have been studied in villages of Trois-Sauts on the upper Oyapock River (French Guiana). During three sojourns amounting to a sampling effor...
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The commensal small non-volant mammals found in traditional houses of Wayampi Amerindians have been studied in villages of Trois-Sauts on the upper Oyapock River (French Guiana). During three sojourns amounting to a sampling effort of 1047 trap-nights, a total of 47 stilt houses were sampled, yielding 119 small non-volant mammals of 8 species (6 rodents and 2 opossums). The sigmodontine rodent Nectomys rattus was the most abundant species (58 individuals), followed in decreasing abundance by Oecomys bicolor, Marmo sa murina, Oecomys rutilus, Hylaeamys megacephalus, Proechimys cuvieri, Makalata didelphoides and Philander opossum. On average, each house yielded 2.5 animals (range: 0-5); Oecomys bicolor (n=21) and O. rutilus (n=10) were caught in the same stilt house on five occasions. This investigation is apparently the first.published study describing the commensal non-volant mammals associated with a traditional Amerindian community in the Guiana Shield or in Amazonia.
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In this paper, we present the lectotypification of 57 names of ferns and lycophytes for a total of 60 taxa studied. These names belong to species that occur mainly in the Guianas and other localities in the Neotropical region. Mos...
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In this paper, we present the lectotypification of 57 names of ferns and lycophytes for a total of 60 taxa studied. These names belong to species that occur mainly in the Guianas and other localities in the Neotropical region. Most of these names (46) are synonyms and others (14) are names in use. Among these 57 lectotypifications, 45 are here designated, 10 of them were already made by previous authors, but were overlooked by subsequent authors or for which we give additional information, and two others are second-step lectotypifications [Adiantum tomentosum and Pteris biformis). Two holotypes have been confirmed, and for one name [Adiantum petiolatum), typification was not possible to make because we did not find the original material. For all cited types, we provide information about the presence of barcode or accession numbers. This information allows easy localization of the type specimens and their image through the Word Wide Web.
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Type specimens of some of Caporiacco's Neotropical species are revised. The taxonomy of his species from French Guiana, whose type specimens are lost, is considered. The types of Corythalia hadzji Caporiacco, 1947, Corythalia luct...
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Type specimens of some of Caporiacco's Neotropical species are revised. The taxonomy of his species from French Guiana, whose type specimens are lost, is considered. The types of Corythalia hadzji Caporiacco, 1947, Corythalia luctuosa Caporiacco 1954, Hypaeus barromachadoi Caporiacco,1947 and Naubolus melloleitaoi Caporiacco,1947 are redescribed.The following new synonymies are established: Freya guianensis Caporiacco,1947 = Chira spinipes (Taczanowski, 1871) syn. nov; Hypaeus bivittatus Caporiacco,1947 = Hypaeus barromachadoi Caporiacco,1947 syn. nov. New combinations are:Agelista petrusewiczi Caporiacco,1947 = Noegus petrusewiczi (Caporiacco,1947) comb. nov;Albionella chickeringi Caporiacco, 1954 = Mago chickeringi (Caporiacco,1954) comb. nov;Asaracus pauciaculeis Caporiacco,1947 = Mago pauciaculeis (Caporiacco, 1947) comb. nov; Cerionesta leucomystax Caporiacco,1947 = Sassacus leucomystax (Caporiacco,1947) comb. nov; Lapsias guianensis Caporiacco,1947 = Cobanus guianensis (Caporiacco,1947) comb. nov; Phiale modestissima Caporiacco,1947 = Asaracus modestissimus (Caporiacco,1947) comb. nov. The species Noegus lodovicoi sp. nov is also described, based on an ex-syntype of Agelista petrusewiczi. The following nominal species are considered species inquirendae: Albionella guianensis Caporiacco,1954, Alcmena trifasciata Caporiacco,1954, Amycus effeminatus Caporiacco,1954, Capidava variegate Caporiacco, 1954, Corythalia variegata Caporiacco,1954, Dendryphantes coccineocinctus Caporiacco,1954, Dendryphantes gertschi Caporiacco, 1947, Dendryphantes spinosissimus Caporiacco,1954, Ilargus modestus Caporiacco,1947, Lapsias melanopygus Caporiacco,1947 = Frigga melanopygus (Caporiacco,1947) comb. nov, Lurio splendidissimus Caporiacco, 1954, Nagaina modesta Caporiacco, 1954, Amycus patellaris (Caporiacco,1954), Phidippus triangulifer Caporiacco,1954 and Tutelina iridea Caporiacco,1954.
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In a taxonomic study of yeasts that have been isolated in French Guiana and Thailand, five yeast strains isolated from plants were found to belong to the Yamadazyma clade of Saccharomycotina. On the basis of morphology, physiology...
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In a taxonomic study of yeasts that have been isolated in French Guiana and Thailand, five yeast strains isolated from plants were found to belong to the Yamadazyma clade of Saccharomycotina. On the basis of morphology, physiology and the nucleotide divergence in the Dl /D2 domain of the 26S nuclear ribosomal RNA (nrRNA) gene, as well as the internal transcribed spacers (ITS) domain of the nrRNA gene operon, these strains were identified to represent three novel species in this teleomorphic clade. An additional isolate, that is publicly available from the CBS yeast collection and isolated from Taiwan, was found to be similar to one of the novel spe- . cies described from Thailand. Yeast species belonging to the Yamadazyma clade have previously been described as members of the Candida membranifaciens clade. These species are widely distributed and were isolated from diverse habitats, including water, plants, animals and guts of insects and termites. In the present study the ITS region is shown to be a valuable region for species identification within this clade, and the novel species proposed are Candida vaughaniae (ex-type strain CBS 8583), Candida khao-thaluensis (ex-type strain CBS 8535) and Candida tallmaniae (ex-type strain CBS 8575).
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