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101.
Boris L. Blotto José J. Nuñez Néstor G. Basso Carmen A. Úbeda Ward C. Wheeler Julián Faivovich 《Cladistics : the international journal of the Willi Hennig Society》2013,29(2):113-131
The frog clade composed of the alsodid genera Alsodes + Eupsophus is the most species‐rich of the Patagonian endemic frog clades, including nearly 31 of the slightly more than 50 species of that region. The biology of this group of frogs is poorly known, its taxonomy quite complex (particularly Alsodes), and its diversity in chromosome number striking when compared with other frogs (collectively, there are species having 2n = 22, 2n = 26, 2n = 28, 2n = 30 or 2n = 34). We present a phylogenetic analysis of this Patagonian frog clade based on mitochondrial and nuclear gene sequences. We sequenced five mitochondrial genes (cytochrome b, cytochrome oxidase I, 12S, 16S, NADH dehydrogenase subunit 1) with three intervening tRNAs, and fragments of three nuclear genes (seven in absentia homolog 1, rhodopsin exon 1, RAG‐1), for a maximum of 6510 bp for multiple specimens from 26 of the 31 species. We recovered Eupsophus as polyphyletic, with E. antartandicus, E. sylvaticus, and E. taeniatus in Batrachylidae, in accordance with most previous hypotheses. Based on this result, we transfer E. antartandicus and E. taeniatus back to Batrachyla, and E. sylvaticus to Hylorina (resurrected from the synonymy of Eupsophus), remediating the paraphyly of Eupsophus. Our results strongly corroborate the monophyly of Alsodes + Eupsophus (sensu stricto), the individual monophyly of these genera, and the monophyly of the species groups of Eupsophus. They also show the non‐monophyly of all non‐monotypic species groups of Alsodes proposed in the past. Our results expose several taxonomic problems particularly in Alsodes, and to a lesser extent in Eupsophus. This phylogenetic context suggests a rich evolutionary history of karyotypic diversification in the clade, in part corroborating previous hypotheses. In Alsodes, we predict three independent transformations of chromosome number from the plesiomorphic 2n = 26. All these, strikingly, involve increments or reductions of pairs of haploid chromosomes. Finally, the phylogenetic pattern recovered for Alsodes and Eupsophus suggests a trans‐Andean origin and diversification of the group, with multiple, independent ingressions over cis‐Andean regions. 相似文献
102.
German Andres Estrada Vera Lúcia Divan Baldani Danilo Messias de Oliveira Segundo Urquiaga José Ivo Baldani 《Plant and Soil》2013,369(1-2):115-129
Background and Aims
Plant growth-promoting bacteria, mainly diazotrophs and phosphate solubilizers, can reduce the use of chemical fertilizers for rice crops. Here, diazotrophic bacteria isolated from rice were screened for their ability to solubilize inorganic P (Pi) in vitro and in association with rice plants cultivated in pots.Methods
Forty-nine isolates were tested for the ability to solubilize Pi on NBRIP and GL agar plate media and seven selected strains were further evaluated in NBRIP liquid medium. Three of these strains were inoculated in rice plants grown in soil pots containing 15N-labeled fertilizer and two sources of P: tricalcium phosphate (TCP) or simple superphosphate (SSP). The dry matter, yield, N, P, and the 15N content accumulated in plant tissues were measured at 135 days after planting.Results
Seven strains belonging to the genera Herbaspirillum and Burkholderia formed a halo of solubilized Pi on agar plates. The Burkholderia strains showed peak soluble P (around 200 mg P L?1) on the fifth day when grown in NBRIP liquid medium for 14 days. Inoculation of Herbaspirillum strains (H18, ZA15) and a Burkholderia vietaminensis strain (AR114) increased rice grain yield from 33 to 47 % with TCP and 18 to 44 % with TSS, respectively. The bacterial inoculation led to enhanced N-use efficiency of the 15N-labeled fertilizer.Conclusion
These results suggest that the selection and use of P-solubilizing diazotrophic bacteria are a good strategy to promote P solubilization and/or N use efficiency in rice plants. 相似文献103.
Cyril Montoya Adrian Balasescu Sébastien Joannin Vincent Ollivier Jérémie Liagre Samvel Nahapetyan Ruben Ghukasyan David Colonge Boris Gasparyan Christine Chataigner 《Journal of human evolution》2013
The open-air site of Kalavan 1 is located in the Aregunyats mountain chain (at 1640 m above sea level) on the northern bank of Lake Sevan. It is the first Upper Palaeolithic site excavated in Armenia. Led by an Armenian-French team, several excavations (2005–2009) have revealed a well preserved palaeosoil, dated to around 14,000 BP (years before present), containing fauna, lithic artefacts, as well as several hearths and activity areas that structure the settlement. The initial studies enable placement of the site in its environment and justify palaeoethnological analysis of the Epigravettian human groups of the Lesser Caucasus. 相似文献
104.
Multi-environment analysis and improved mapping of a yield-related QTL on chromosome 3B of wheat 总被引:1,自引:0,他引:1
Julien Bonneau Julian Taylor Boris Parent Dion Bennett Matthew Reynolds Catherine Feuillet Peter Langridge Diane Mather 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2013,126(3):747-761
Improved mapping, multi-environment quantitative trait loci (QTL) analysis and dissection of allelic effects were used to define a QTL associated with grain yield, thousand grain weight and early vigour on chromosome 3BL of bread wheat (Triticum aestivum L.) under abiotic stresses. The QTL had pleiotropic effects and showed QTL x environment interactions across 21 diverse environments in Australia and Mexico. The occurrence and the severity of water deficit combined with high temperatures during the growing season affected the responsiveness of this QTL, resulting in a reversal in the direction of allelic effects. The influence of this QTL can be substantial, with the allele from one parent (RAC875) increasing grain yield by up to 12.5 % (particularly in environments where both heat and drought stress occurred) and the allele from the other parent (Kukri) increasing grain yield by up to 9 % in favourable environments. With the application of additional markers and the genotyping of additional recombinant inbred lines, the genetic map in the QTL region was refined to provide a basis for future positional cloning. 相似文献
105.
Kethika Kulleperuma Susan M.E. Smith Deri Morgan Boris Musset John Holyoake Nilmadhab Chakrabarti Vladimir V. Cherny Thomas E. DeCoursey Régis Pomès 《The Journal of general physiology》2013,141(4):445-465
The topological similarity of voltage-gated proton channels (HV1s) to the voltage-sensing domain (VSD) of other voltage-gated ion channels raises the central question of whether HV1s have a similar structure. We present the construction and validation of a homology model of the human HV1 (hHV1). Multiple structural alignment was used to construct structural models of the open (proton-conducting) state of hHV1 by exploiting the homology of hHV1 with VSDs of K+ and Na+ channels of known three-dimensional structure. The comparative assessment of structural stability of the homology models and their VSD templates was performed using massively repeated molecular dynamics simulations in which the proteins were allowed to relax from their initial conformation in an explicit membrane mimetic. The analysis of structural deviations from the initial conformation based on up to 125 repeats of 100-ns simulations for each system reveals structural features consistently retained in the homology models and leads to a consensus structural model for hHV1 in which well-defined external and internal salt-bridge networks stabilize the open state. The structural and electrostatic properties of this open-state model are compatible with proton translocation and offer an explanation for the reversal of charge selectivity in neutral mutants of Asp112. Furthermore, these structural properties are consistent with experimental accessibility data, providing a valuable basis for further structural and functional studies of hHV1. Each Arg residue in the S4 helix of hHV1 was replaced by His to test accessibility using Zn2+ as a probe. The two outermost Arg residues in S4 were accessible to external solution, whereas the innermost one was accessible only to the internal solution. Both modeling and experimental data indicate that in the open state, Arg211, the third Arg residue in the S4 helix in hHV1, remains accessible to the internal solution and is located near the charge transfer center, Phe150. 相似文献
106.
Yasmin Rubio-Palis Mariapia Bevilacqua Domingo Alberto Medina Jorge Ernesto Moreno Lya Cárdenas Víctor Sánchez Yarys Estrada William Anaya ángela Martínez 《Memórias do Instituto Oswaldo Cruz》2013,108(2):220-228
To explore the effects of deforestation and resulting differences in vegetation and land cover on entomological parameters, such as anopheline species composition, abundance, biting rate, parity and entomological inoculation rate (EIR), three villages were selected in the Lower Caura River Basin, state of Bolívar, Venezuela. All-night mosquito collections were conducted between March 2008-January 2009 using CDC light traps and Mosquito Magnet(r) Liberty Plus. Human landing catches were performed between 06:00 pm-10:00 pm, when anophelines were most active. Four types of vegetation were identified. The Annual Parasite Index was not correlated with the type of vegetation. The least abundantly forested village had the highest anopheline abundance, biting rate and species diversity. Anopheles darlingi and Anopheles nuneztovari were the most abundant species and were collected in all three villages. Both species showed unique biting cycles. The more abundantly forested village of El Palmar reported the highest EIR. The results confirmed previous observations that the impacts of deforestation and resulting changes in vegetation cover on malaria transmission are complex and vary locally. 相似文献
107.
Nil Rahola Jér?me Depaquit Boris Kevin Makanga Christophe Paupy 《Memórias do Instituto Oswaldo Cruz》2013,108(7):845-849
During a research project aimed at the study of the Culicinae fauna of Gabon and
carried out in the National Park of La Lopé, we captured an unknown sandfly male
specimen (genus Phlebotomus) by CDC miniature light trap
belonging to a new species for Science. Furthermore, the originality of his
genitalia does not allow us to include this species in one of the existing
subgenus, thus in this paper we propose the creation of a new subgenus, as
Phlebotomus (Legeromyia) multihamatus sp. nov., subg. nov.
described from the National Park of La Lopé, through one male captured with CDC
miniature light trap. A new species and a new subgenus of sandfly is
characterised by a short style with three spines, a paramere wearing a basal
hook as well as a basal pouch and the absence of basal lobe on the coxite. The
originality of the genitalia of the male gives way to discussion about potential
primary homologies between P. multihamatus sp. nov. and
Phlebotomus (Abonnencius) fortunatarum, Phlebotomus
(Anaphlebotomus) stantoni and Phlebotomus (Euphlebotomus)
argentipes, which should be verified for future studies. The
discovery of this new species in Gabon must encourage the study of sandflies in
this country. 相似文献
108.
Pedro X. Astudillo Gabriela M. Samaniego Pedro J. Machado Juan M. Aguilar Boris A. Tinoco Catherine H. Graham 《Studies on Neotropical Fauna and Environment》2013,48(3):204-212
National parks are an important tool for conserving biodiversity, particularly in areas of high biodiversity and endemism such as the tropical Andes. However, national parks often face a variety of stressors related to recreation, road construction and illegal extraction of natural resources. Unfortunately, the influence of these stressors for biodiversity is rarely well documented. Cajas National Park in Ecuador is no exception. Despite being traversed by the Cuenca-Molleturo-Naranjal road, effects of the road construction on biodiversity have not been determined. We therefore assessed the influence of road proximity on bird species richness and abundance as well as composition of bird habitat groups in Cajas National Park using transect walks at 25 m and 250 m distance to the road (overall 18 transects, each 1 km length). In total, we recorded 1110 individuals of 28 páramo bird species. Overall species richness did not differ between transects near and far from the road. Nevertheless, the average abundance of shrubby páramo species was significantly higher far from the road than near the road (Far = 36, Near = 25). Moreover, we found a tendency towards differences in the composition of bird habitat groups between transects near and far from the road. One aspect potentially driving the observed patterns was the increasing proportion of planted non-native woody tree species within páramo grassland near the road, which may have caused reduced abundances of shrubby páramo bird species there. While roads represented a clear impact on the composition of bird species in the páramo, the major effect seems to be driven by the introduction of non-native plant species along the roadside. In order to reduce the impact of roads to a minimum, we suggest that park managers should control the introduction of such plant species. 相似文献
109.
Veronika Slancarova Jana Zdanska Bohuslav Janousek Martina Talianova Christian Zschach Jitka Zluvova Jiri Siroky Viera Kovacova Hana Blavet Jiri Danihelka Bengt Oxelman Alex Widmer Boris Vyskot 《Evolution; international journal of organic evolution》2013,67(12):3669-3677
The plant genus Silene has become a model for evolutionary studies of sex chromosomes and sex‐determining mechanisms. A recent study performed in Silene colpophylla showed that dioecy and the sex chromosomes in this species evolved independently from those in Silene latifolia, the most widely studied dioecious Silene species. The results of this study show that the sex‐determining system in Silene otites, a species related to S. colpophylla, is based on female heterogamety, a sex determination system that is unique among the Silene species studied to date. Our phylogenetic data support the placing of S. otites and S. colpophylla in the subsection Otites and the analysis of ancestral states suggests that the most recent common ancestor of S. otites and S. colpophylla was most probably dioecious. These observations imply that a switch from XX/XY sex determination to a ZZ/ZW system (or vice versa) occurred in the subsection Otites. This is the first report of two different types of heterogamety within one plant genus of this mostly nondioecious plant family. 相似文献
110.
T. Mitchell Aide Matthew L. Clark H. Ricardo Grau David López‐Carr Marc A. Levy Daniel Redo Martha Bonilla‐Moheno George Riner María J. Andrade‐Núñez María Muñiz 《Biotropica》2013,45(2):262-271
Forest cover change directly affects biodiversity, the global carbon budget, and ecosystem function. Within Latin American and the Caribbean region (LAC), many studies have documented extensive deforestation, but there are also many local studies reporting forest recovery. These contrasting dynamics have been largely attributed to demographic and socio‐economic change. For example, local population change due to migration can stimulate forest recovery, while the increasing global demand for food can drive agriculture expansion. However, as no analysis has simultaneously evaluated deforestation and reforestation from the municipal to continental scale, we lack a comprehensive assessment of the spatial distribution of these processes. We overcame this limitation by producing wall‐to‐wall, annual maps of change in woody vegetation and other land‐cover classes between 2001 and 2010 for each of the 16,050 municipalities in LAC, and we used nonparametric Random Forest regression analyses to determine which environmental or population variables best explained the variation in woody vegetation change. Woody vegetation change was dominated by deforestation (?541,835 km2), particularly in the moist forest, dry forest, and savannas/shrublands biomes in South America. Extensive areas also recovered woody vegetation (+362,430 km2), particularly in regions too dry or too steep for modern agriculture. Deforestation in moist forests tended to occur in lowland areas with low population density, but woody cover change was not related to municipality‐scale population change. These results emphasize the importance of quantitating deforestation and reforestation at multiple spatial scales and linking these changes with global drivers such as the global demand for food. 相似文献