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Antananarivo, Madagascar

Rasamoelina-Andriamanivo H.,FOFIFA | Rasamoelina-Andriamanivo H.,University of Monastir | Porphyre V.,CIRAD | Jambou R.,Institute Pasteur Of Madagascar
Trends in Parasitology | Year: 2013

Taenia solium cysticercosis is a zoonosis of public health importance in areas where the disease is endemic, with significant economic impacts on human health and the swine industry. Several gaps remain in the epidemiology of the parasite and the strategies of control in developing countries. We detail the key factors to consider in Madagascar in terms of the porcine husbandry system, Taenia transmission cycle, and diagnosis of cysticercosis in pigs, in order to better estimate the sanitary and economic impacts of this parasitic disease as well as to define an integrated control program. © 2013 Elsevier Ltd.

Roncal J.,Memorial University of Newfoundland | Roncal J.,IRD Montpellier | Guyot R.,IRD Montpellier | Hamon P.,IRD Montpellier | And 7 more authors.
Molecular Genetics and Genomics | Year: 2016

The completion of the genome assembly for the economically important coffee plant Coffea canephora (Rubiaceae) has allowed the use of bioinformatic tools to identify and characterize a diverse array of transposable elements (TEs), which can be used in evolutionary studies of the genus. An overview of the copy number and location within the C. canephora genome of four TEs is presented. These are tested for their use as molecular markers to unravel the evolutionary history of the Millotii Complex, a group of six wild coffee (Coffea) species native to Madagascar. Two TEs from the Gypsy superfamily successfully recovered some species boundaries and geographic structure among samples, whereas a TE from the Copia superfamily did not. Notably, species occurring in evergreen moist forests of eastern and southeastern Madagascar were divergent with respect to species in other habitats and regions. Our results suggest that the peak of transpositional activity of the Gypsy and Copia TEs occurred, respectively, before and after the speciation events of the tested Madagascan species. We conclude that the utilization of active TEs has considerable potential to unravel the evolutionary history and delimitation of closely related Coffea species. However, the selection of TE needs to be experimentally tested, since each element has its own evolutionary history. Different TEs with similar copy number in a given species can render different dendrograms; thus copy number is not a good selection criterion to attain phylogenetic resolution. © 2015, Springer-Verlag Berlin Heidelberg.

Razafinarivo N.J.,IRD Montpellier | Guyot R.,IRD Montpellier | Davis A.P.,Royal Botanic Gardens | Couturon E.,IRD Montpellier | And 8 more authors.
Annals of Botany | Year: 2013

Background and Aims The coffee genus (Coffea) comprises 124 species, and is indigenous to the Old World Tropics. Due to its immense economic importance, Coffea has been the focus of numerous genetic diversity studies, but despite this effort it remains insufficiently studied. In this study the genetic diversity and genetic structure of Coffea across Africa and the Indian Ocean islands is investigated. Methods Genetic data were produced using 13 polymorphic nuclear microsatellite markers (simple sequence repeats, SSRs), including seven expressed sequence tag-SSRs, and the data were analysed using model-and non-model-based methods. The study includes a total of 728 individuals from 60 species. Key Results Across Africa and the Indian Ocean islands Coffea comprises a closely related group of species with an overall pattern of genotypes running from west to east. Genetic structure was identified in accordance with pre-determined geographical regions and phylogenetic groups. There is a good relationship between morpho-taxonomic species delimitations and genetic units. Genetic diversity in African and Indian Ocean Coffea is high in terms of number of alleles detected, and Madagascar appears to represent a place of significant diversification in terms of allelic richness and species diversity. Conclusions Cross-species SSR transferability in African and Indian Ocean islands Coffea was very efficient. On the basis of the number of private alleles, diversification in East Africa and the Indian Ocean islands appears to be more recent than in West and West-Central Africa, although this general trend is complicated in Africa by the position of species belonging to lineages connecting the main geographical regions. The general pattern of phylogeography is not in agreement with an overall east to west (Mascarene, Madagascar, East Africa, West Africa) increase in genome size, the high proportion of shared alleles between the four regions or the high numbers of exclusive shared alleles between pairs or triplets of regions. © The Author 2012.

Andrianoelisoa H.,FOFIFA | Andrianoelisoa H.,University of Antananarivo | Menut C.,Equipe Glyco et nanovecteurs pour le ciblage therapeutique | Danthu P.,CIRAD - Agricultural Research for Development | Danthu P.,University of Antananarivo
Phytotherapie | Year: 2012

For many years, various articles alerted on confusions concerning the commercial batches of essential oils of Ravensara aromatica and Ravintsara (Cinnamomum camphora). Recent work has, moreover, highlighted the existence of five different essential oils chemotypes from the species Ravensara aromatica, which still adds to the confusion. The fifth chemotype identified is described for the first time in this article. The purpose of this research was to check the continuance of this confusion among the essential oils sold in Madagascar and in the North countries. Thirty four commercial batches of essential oils whose labelling refers to Ravensara or Ravintsara were gathered between 2009 and 2011. The information related to the label was analyzed and the chemical composition of the samples was determined by gas chromatography, gas chromatography coupled with mass spectrometry and compared with reference samples. The results show that the essential oils sold in Madagascar under the designation of Ravintsara and Ravensara aromatica/Ravensara anisata are authentic volatile extracts of Ravintsara and Ravensara. In the North countries, the situation is different. Oils of Ravintsara are generally well labelled. But among fourteen samples labelled Ravensara aromatica or Ravensara anisata, only five were authentic essential oils of Ravensara. This confusion, associated with the natural chemical variability of the essential oils of Ravensara and with the problems related to the exploitation of an endemic species of a south country (threat on the resource, weak remuneration of the collectors), raises the question of the durable exploitation of this species. © Springer-Verlag France 2012.

Rakotomalala M.,British Petroleum | Pinel-Galzi A.,Montpellier University | Mpunami A.,Mikocheni Agricultural Research Institute | Randrianasolo A.,CRRSO | And 3 more authors.
Virus Research | Year: 2013

Rice yellow mottle virus (RYMV), of the genus Sobemovirus, is a major threat to rice cultivation in Africa. Long range transmission of RYMV, difficult to study experimentally, is inferred from a detailed analysis of the molecular diversity of the virus in Madagascar and in the Zanzibar Archipelago (Zanzibar and Pemba Islands; Tanzania) compared with that found elsewhere in Africa. A unique successful introduction of RYMV to Madagascar, which is ca. 400. km from mainland Africa, contrasted with recurrent introductions of the virus to the Zanzibar Archipelago, ca. 40. km from the East African coast. Accordingly, RYMV dispersal over distances of hundreds of kilometers is rare whereas spread of the virus over distances of tens of kilometers is relatively frequent. The dates of introduction of RYMV to Madagascar and to Pemba Island were estimated from three sets of ORF4 sequences of virus isolates collected between 1966 and 2011. They were compared with the dates of the first field detection in Madagascar (1989) and in Pemba Island (1990). The estimates did not depend substantially on the data set used or on the evolutionary model applied and their credible intervals were narrow. The estimated dates are recent - 1978 (1969-1986) and 1985 (1977-1993) in Madagascar and in Pemba Island, respectively - compared to the early diversification of RYMV in East Africa ca. 200 years ago. They predated by 5-10 years the first field detections in these islands. The interplay between virus sources, rice cultivation and long range dispersal which led to RYMV emergence and spread is enlightened. © 2012 Elsevier B.V.

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