Losfeld G.,CNRS Center of Evolutionary and Functional Ecology |
Escande V.,CNRS Center of Evolutionary and Functional Ecology |
Escande V.,French Environment and Energy Management Agency |
Jaffre T.,Institute Of Recherche Pour Le Developpement |
And 2 more authors.
Chemosphere | Year: 2012
Herein, we explore the outlines of an innovative method based on the chemical recovery of metal-rich biomass produced in phytoextraction technologies. Taking advantage of the adaptive capacity of some New Caledonian plants to hyperaccumulate Ni2+ cations in their aerial parts, this technique is based on the direct use of metals derived from plants as " Lewis acid" catalysts in organic chemistry. Metallic cations contained in New Caledonian nickel hyperaccumulators are recovered through a simple cost-effective process and serve the preparation of heterogeneous catalysts used in synthetic transformations allowing access to molecules with high added-value. The design of all processes is in line with the principles of green chemistry; it is adapted to the new economic constraints; it offers a new relevant outlet for metal-rich biomass; and it represents an alternative to non-renewable mineral materials. © 2012 Elsevier Ltd.
Barthe S.,University of the French West Indies and Guiana |
Gugerli F.,Swiss Federal Institute of forest |
Barkley N.A.,Plant Genetic Resources Conservation Unit |
Maggia L.,Institute Agronomique neo Caledonien |
And 2 more authors.
PLoS ONE | Year: 2012
Simple sequence repeat (SSR) markers are widely used tools for inferences about genetic diversity, phylogeography and spatial genetic structure. Their applications assume that variation among alleles is essentially caused by an expansion or contraction of the number of repeats and that, accessorily, mutations in the target sequences follow the stepwise mutation model (SMM). Generally speaking, PCR amplicon sizes are used as direct indicators of the number of SSR repeats composing an allele with the data analysis either ignoring the extent of allele size differences or assuming that there is a direct correlation between differences in amplicon size and evolutionary distance. However, without precisely knowing the kind and distribution of polymorphism within an allele (SSR and the associated flanking region (FR) sequences), it is hard to say what kind of evolutionary message is conveyed by such a synthetic descriptor of polymorphism as DNA amplicon size. In this study, we sequenced several SSR alleles in multiple populations of three divergent tree genera and disentangled the types of polymorphisms contained in each portion of the DNA amplicon containing an SSR. The patterns of diversity provided by amplicon size variation, SSR variation itself, insertions/deletions (indels), and single nucleotide polymorphisms (SNPs) observed in the FRs were compared. Amplicon size variation largely reflected SSR repeat number. The amount of variation was as large in FRs as in the SSR itself. The former contributed significantly to the phylogenetic information and sometimes was the main source of differentiation among individuals and populations contained by FR and SSR regions of SSR markers. The presence of mutations occurring at different rates within a marker's sequence offers the opportunity to analyse evolutionary events occurring on various timescales, but at the same time calls for caution in the interpretation of SSR marker data when the distribution of within-locus polymorphism is not known.
PubMed | Jardin Botanico Nacional Dr. Rafael Ma. Moscoso, Institute of Jamaica, Federal University of Vales do Jequitinhonha and Mucuri, University of Sao Paulo and 13 more.
Type: | Journal: Molecular phylogenetics and evolution | Year: 2017
Myrteae (c. 2500 species; 51 genera) is the largest tribe of Myrtaceae and an ecologically important groups of angiosperms in the Neotropics. Systematic relationships in Myrteae are complex, hindering conservation initiatives and jeopardizing evolutionary modelling. A well-supported and robust phylogenetic hypothesis was here targeted towards a comprehensive understanding of the relationships within the tribe. The resultant topology was used as a base for key evolutionary analyses such as age estimation, historical biogeography and diversification rate patterns. One nuclear (ITS) and seven chloroplast (psbA-trnH, matK, ndhF, trnl-trnF, trnQ-rps16, rpl16 and rpl32-trnL) DNA regions for 115 taxa representing 46 out of the 51 genera in the tribe were accessed and analysed using maximum likelihood and Bayesian inference tools for phylogenetic reconstruction. Dates of diversification events were estimated and contrasted using two distinct fossil sets (macro and pollen) in BEAST. The subsequent dated phylogenies were compared and analysed for biogeographical patterns using BioGeoBEARS and diversification rates using BAMM. Myrteae phylogeny presents strong statistical support for three major clades within the tribe: Australasian group, Myrtus group and Main Neotropical Lineage. Dating results from calibration using macrofossil are an average of 20 million years older and show an early Paleocene origin of Myrteae, against a mid-Eocene one from the pollen fossil calibration. Biogeographic analysis shows the origin of Myrteae in Zealandia in both calibration approaches, followed by a widespread distribution throughout the still-linked Gondwana continents and diversification of Neotropical endemic lineages by later vicariance. Best configuration shift indicates three points of acceleration in diversification rates, all of them occurring in the Main Neotropical Lineage. Based on the reconstructed topology, several new taxonomic placements were recovered, including: the relative position of Myrtus communis, the placement of the Blepharocalyx group, the absence of generic endemism in the Caribbean, and the paraphyletism of the former Pimenta group. Distinct calibration approaches affect biogeography interpretation, increasing the number of necessary long distance dispersal events in the topology with older nodes. It is hypothesised that biological intrinsic factors such as modifications of embryo type and polyploidy might have played a role in accelerating shifts of diversification rates in Neotropical lineages. Future perspectives include formal subtribal classification, standardization of fossil calibration approaches and better links between diversification shifts and trait evolution.
Gateble G.,Institute Agronomique Neo Caledonien |
Munzinger J.,IRD Montpellier
Adansonia | Year: 2012
Oxera pancheri Dubard, a name placed in synonymy under Oxera sulfurea Dubard in the revision of the genus in 1999 and 2004, is rehabilitated. Newly collected specimens, especially the first material ever with fruits, supports the recognition of this species, first described in 1906. Morphologically, O. pancheri differs from O. sulfurea by its racemiform inflorescences, its stamens and style slightly exserted and its velutinous fruits. Oxera pancheri seems morphologically closer (based on inflorescence type, shape and characteristics of the mericarps, juvenile foliage) to O. microcalyx Guillaumin than to O. sulfurea. Oxera pancheri is endemic to the southern part of New Caledonia's main island "Grande-Terre", growing on ultramafic substrates. The limited geographic distribution of this species and the threats to its remaining populations lead us to assign a provisional conservation status of Endangered using the IUCN Red List criteria. © Publications Scientifiques du Muséum national d'Histoire naturelle.
Viennois G.,French National Center for Scientific Research |
Barbier N.,IRD Montpellier |
Fabre I.,Institute Agronomique Neo Caledonien |
Couteron P.,IRD Montpellier
Biogeosciences | Year: 2013
The characterization of leaf phenology in tropical forests is of major importance for forest typology as well as to improve our understanding of earth-atmosphere-climate interactions or biogeochemical cycles. The availability of satellite optical data with a high temporal resolution has permitted the identification of unexpected phenological cycles, particularly over the Amazon region. A primary issue in these studies is the relationship between the optical reflectance of pixels of 1 km or more in size and ground information of limited spatial extent. In this paper, we demonstrate that optical data with high to very-high spatial resolution can help bridge this scale gap by providing snapshots of the canopy that allow discernment of the leaf-phenological stage of trees and the proportions of leaved crowns within the canopy. We also propose applications for broad-scale forest characterization and mapping in West-Central Africa over an area of 141 000 km2.
Eleven years of the Moderate Resolution Imaging Spectroradiometer (MODIS) Enhanced Vegetation Index (EVI) data were averaged over the wet and dry seasons to provide a data set of optimal radiometric quality at a spatial resolution of 250 m. Sample areas covered at a very-high (GeoEye) and high (SPOT-5) spatial resolution were used to identify forest types and to quantify the proportion of leaved trees in the canopy. The dry-season EVI was positively correlated with the proportion of leaved trees in the canopy. This relationship allowed the conversion of EVI into canopy deciduousness at the regional level. On this basis, ecologically important forest types could be mapped, including young secondary, open Marantaceae, Gilbertiodendron dewevrei and swamp forests. We show that in West-Central African forests, a large share of the variability in canopy reflectance, as captured by the EVI, is due to variation in the proportion of leaved trees in the upper canopy, thereby opening new perspectives for biodiversity and carbon-cycle applications. © Author(s) 2013. CC Attribution 3.0 License.
Daval N.,Cabinet Veterinaire du Regain |
Marchal C.,Service des Laboratoires Officiels Veterinaires |
Guillaumot L.,Institute Pasteur Of Nouvelle Caledonie |
Hue T.,Institute Agronomique Neo Caledonien |
And 3 more authors.
Parasites and Vectors | Year: 2016
Background: Canine leishmaniasis (CanL), a parasitic zoonotic disease caused by Leishmania infantum and usually transmitted by phlebotomine sandflies, has rarely been reported in Pacific islands, which have been regarded until now as leishmaniasis-free territory. Here, we report the first autochthonous CanL case in New Caledonia (south-western Pacific) and the investigations carried out 1) to determine how infection was introduced into and transmitted among these dogs and 2) to assess the risks to animal and public health. Methods: Extensive epidemiological and entomological investigations in and around the focus were carried out. Leishmaniasis infection was confirmed by histopathology, indirect fluorescent antibody test, real-time PCR, and culture. Parasite strain was typed by the isoenzymatic technique. Results: The survey revealed close contacts between the autochthonous dog and two infected bitches imported from Spain, but failed to find any possible vector or disease spreading to other animals or humans. L. infantum zymodeme MON-1, the most frequent type in the Mediterranean basin, was identified. Although transplacental and venereal transmissions could not be excluded, the evidence was in favour of non-vectorial, direct dog-to-dog transmission. Conclusions: This study corroborates the possibility of non-vectorial routes (transplacental, venereal, and direct dog-to-dog) of canine leishmaniasis transmission in New Caledonia and raises the debate of relevant test requirements and diagnostic sensitivity prior to importation of dogs in Leishmania-free regions. New leishmaniasis control measures and recommendations to avoid future CanL introduction on the island are discussed. © 2016 Daval et al.
Lebouvier N.,University of New Caledonia |
Hue T.,Institute Agronomique Neo Caledonien |
Hnawia E.,University of New Caledonia |
Lesaffre L.,University of New Caledonia |
And 2 more authors.
Parasitology Research | Year: 2013
The aim of the present study was to demonstrate acaricidal activity on the cattle tick Rhipicephalus (Boophilus) microplus of essential oils from endemic conifers of New Caledonia in the context of the development of natural alternatives. Acaricidal activity of essential oils extracted from resin and heartwood of five endemic conifers of New Caledonia (Araucaria columnaris, Agathis moorei, Agathis ovata, Callitris sulcata, and Neocallitropsis pancheri) was evaluated on 14- to 21-day-old Rhipicephalus microplus tick larvae using the Larval Packal Test bioassay. A first screening with 5 % dilute solution was carried out and the oils with 100 % of mortality at this rate were diluted until no activity was shown. The heartwood oils of the two Cupressaceae were the most active with LC50 value of 0.65 % for C. sulcata and 0.55 % for N. pancheri while resin oil of A. columnaris (LC50 = 1.62 %) was the most active of the Araucariaceae family. Negative control (ethanol) was not toxic to the larvae. The chemical composition of essential oil from resin of A. columnaris was analyzed by gas chromatography-mass spectrometry. The essential oil was characterized by high level of sesquiterpene hydrocarbons and oxygenated sesquiterpenes and was composed mainly of aromadendrene (23.1 %) and bicyclogermacrene (16.0 %). In order to compare different plant resources in a sustainable program of natural acaricide, an "essential oil efficiency EOE" can be measured as the ratio between the yield of extraction and LC50 value. This study shows that A. columnaris (EOE = 2.36) and N. pancheri (EOE = 3.51) could provide valuable and effective natural acaricides for control of the cattle tick R. microplus. © 2013 Springer-Verlag Berlin Heidelberg.
Eldin C.,Aix - Marseille University |
Mediannikov O.,Aix - Marseille University |
Davoust B.,Aix - Marseille University |
Davoust B.,French Army Health Service |
And 4 more authors.
Emerging Infectious Diseases | Year: 2011
We detected Rickettsia africae, the agent of African tick-bite fever (ATBF), by amplification of fragments of gltA, ompA, and ompB genes from 3 specimens of Amblyomma loculosum ticks collected from humans and birds in New Caledonia. Clinicians who treat persons in this region should be on alert for ATBF.
Perez J.,Institute Pasteur Of Nouvelle Caledonie |
Brescia F.,Institute Agronomique neo Caledonien |
Becam J.,Institute Pasteur Of Nouvelle Caledonie |
Mauron C.,Institute Pasteur Of Nouvelle Caledonie |
Goarant C.,Institute Pasteur Of Nouvelle Caledonie
PLoS Neglected Tropical Diseases | Year: 2011
Background: Widespread but particularly incident in the tropics, leptospirosis is transmitted to humans directly or indirectly by virtually any Mammal species. However, rodents are recognized as the most important reservoir. In endemic regions, seasonal outbreaks are observed during hot rainy periods. In such regions, hot spots can be evidenced, where leptospirosis is "hyper-endemic", its incidence reaching 500 annual cases per 100,000. A better knowledge of how rodent populations and their Leptospira prevalence respond to seasonal and meteorological fluctuations might help implement relevant control measures. Methodology/Principal Findings: In two tribes in New Caledonia with hyper-endemic leptospirosis, rodent abundance and Leptospira prevalence was studied twice a year, in hot and cool seasons for two consecutive years. Highly contrasted meteorological situations, particularly rainfall intensities, were noted between the two hot seasons studied. Our results show that during a hot and rainy period, both the rodent populations and their Leptospira carriage were higher. This pattern was more salient in commensal rodents than in the sylvatic rats. Conclusions/Significance: The dynamics of rodents and their Leptospira carriage changed during the survey, probably under the influence of meteorology. Rodents were both more numerous and more frequently carrying (therefore disseminating) leptospires during a hot rainy period, also corresponding to a flooding period with higher risks of human exposure to waters and watered soils. The outbreaks of leptospirosis in hyper-endemic areas could arise from meteorological conditions leading to both an increased risk of exposure of humans and an increased volume of the rodent reservoir. Rodent control measures would therefore be most effective during cool and dry seasons, when rodent populations and leptospirosis incidence are low. © 2011 Perez et al.
Gateble G.,Institute Agronomique Neo Caledonien
Acta Horticulturae | Year: 2015
In the past, priorities for selecting species and genera having potential as new floricultural crops have not necessarily been established rationally. Here we propose a simple rational model for doing this and apply it to the New Caledonian flora. Different strategies are required depending on whether the target market is local or international. For the local market, the aim is to develop plants either for the landscape industry or for use in general public gardens, and the task is reasonably straightforward. It involves simply the domestication of showy species that are easily propagated and cultivated under local conditions. The international market is much more competitive and complex, and a more sophisticated procedure is required. A model is proposed that helps to rationalise the selection and prioritisation of genera and species for development. The model is based on a genus' rate of endemism, the attractiveness of its species and the familiarity of taxa already known as ornamentals. The whole is then weighted depending on how easy the genus is to propagate and cultivate. Thus, a genus that is well diversified, that has a high proportion of endemic species, that includes a large number of showy species, and that is not already represented in the international market is perceived as having high ornamental potential. The model developed here has been inferred from experience but has yet to be been validated commercially so no doubt requires further adjustment. Nevertheless it makes a useful start in taking the first steps in providing a rational basis for selecting new ornamental plants. Based on the application of this model to the New Caledonian flora, the most promising genus emerging is Oxera. It fits well with the above selection criteria and most of its species are also easy to propagate and cultivate.