H Lecoq

French National Institute for Agricultural Research, Lutetia Parisorum, Île-de-France, France

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Publications (93)205.27 Total impact

  • [Show abstract] [Hide abstract]
    ABSTRACT: Phytoviruses are highly prevalent in plants worldwide, including vegetables and fruits. Humans, and more generally animals, are exposed daily to these viruses, among which several are extremely stable. It is currently accepted that a strict separation exists between plant and vertebrate viruses regarding their host range and pathogenicity, and plant viruses are believed to infect only plants. Accordingly, plant viruses are not considered to present potential pathogenicity to humans and other vertebrates. Notwithstanding these beliefs, there are many examples where phytoviruses circulate and propagate in insect vectors. Several issues are raised here that question if plant viruses might further cross the kingdom barrier to cause diseases in humans. Indeed, there is close relatedness between some plant and animal viruses, and almost identical gene repertoires. Moreover, plant viruses can be detected in non-human mammals and humans samples, and there are evidence of immune responses to plant viruses in invertebrates, non-human vertebrates and humans, and of the entry of plant viruses or their genomes into non-human mammal cells and bodies after experimental exposure. Overall, the question raised here is unresolved, and several data prompt the additional extensive study of the interactions between phytoviruses and non-human mammals and humans, and the potential of these viruses to cause diseases in humans.
    Viruses 04/2015; 7(4):2074-2098. DOI:10.3390/v7042074 · 3.35 Impact Factor
  • Hervé Lecoq · Nikolaos Katis
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    ABSTRACT: More than 70 well-characterized virus species transmitted by a diversity of vectors may infect cucurbit crops worldwide. Twenty of those cause severe epidemics in major production areas, occasionally leading to complete crop failures. Cucurbit viruses' control is based on three major axes: (i) planting healthy seeds or seedlings in a clean environment, (ii) interfering with vectors activity, and (iii) using resistant cultivars. Seed disinfection and seed or seedling quality controls guarantee growers on the sanitary status of their planting material. Removal of virus or vector sources in the crop environment can significantly delay the onset of viral epidemics. Insecticide or oil application may reduce virus spread in some situations. Diverse cultural practices interfere with or prevent vector reaching the crop. Resistance can be obtained by grafting for soil-borne viruses, by cross-protection, or generally by conventional breeding or genetic engineering. The diversity of the actions that may be taken to limit virus spread in cucurbit crops and their limits will be discussed. The ultimate goal is to provide farmers with technical packages that combine these methods within an integrated disease management program and are adapted to different countries and cropping systems.
    Advances in Virus Research 12/2014; 90:255-96. DOI:10.1016/B978-0-12-801246-8.00005-6 · 4.57 Impact Factor
  • G Romay · H Lecoq · C Desbiez
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    ABSTRACT: Begomoviruses represent one of the most damaging virus groups on many important crops worldwide. In Venezuela, the begomovirus Melon chlorotic mosaic virus (MeCMV) is the major constraint for melon and watermelon production. MeCMV has been associated with the satellite Melon chlorotic mosaic alphasatellite (MeCMA). Full-length genome sequencing of 20 and 35 isolates of MeCMV and MeCMA, respectively, were carried out to estimate their genetic variability. Furthermore, mechanical transmission assays of MeCMV alone or in conjunction with MeCMA were performed. Genetic variation was low among MeCMV isolates which exhibited 97 to 100% nucleotide identity for the DNA-A component and 95 to 100% for the DNA-B component. Alphasatellite isolates were highly variable ranging from 86.5 to 100%. MeCMV isolates were phylogenetically related to begomoviruses belonging to the Squash leaf curl virus (SLCV) clade, while MeCMA isolates were clustered in two subgroups related to alphasatellites from the New World (Cuba and Brazil). MeCMV has a host range restricted to cucurbit species and two experimental hosts: Nicotiana benthamiana and Nicotiana clevelandii. MeCMV can be mechanically transmitted with up to 100% efficiency in melon. The physiological stage of the inoculated organ (cotyledon or leaf) represents a key factor for inoculation efficiency. This result provides a simple and reliable inoculation method to develop extensive screening for MeCMV resistance sources. In addition, the complex MeCMV+MeCMA was mechanically transmitted to melon, N. benthamiana and N. clevelandii plantlets and successfully back-transmitted. To our knowledge, this finding is the first evidence of sap transmission for a begomovirus-satellite complex.This article is protected by copyright. All rights reserved.
    Plant Pathology 12/2014; 64(5). DOI:10.1111/ppa.12342 · 2.12 Impact Factor
  • Gustavo Romay · H. Lecoq · C. Desbiez
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    ABSTRACT: Cucurbit crops are cultivated throughout the world. Melon (Cucumis melo L.), cucumber (Cucumis sativus L.), watermelon (Citrullus lanatus (Thumb.) Mat. et Nak.), squash and pumpkin (Cucurbita spp) are the major crops. In Latin America and the Caribbean islands (LAC) cucurbits are consumed as a part of the daily diet since pre-Columbian times, when some species such as Cucurbita pepo L., Cucurbita moschata Duch. and Cucurbita maxima Duch. were domesticated by American Indians. In LAC, cucurbit crops have become export commodities and a source of income for several countries, in addition to their role in local consumption. The increase of area devoted to cucurbit crops and the intensification of production has led to the emergence of severe viral epidemics that threaten the sustainability of these cultures. This paper reviews the cucurbit viruses described in the region and their impact. In addition, the potential of different measures to control the most frequent cucurbit viruses in LAC is discussed.
    JOURNAL OF PLANT PATHOLOGY 07/2014; 96(2):227-242. DOI:10.4454/JPP.V96I2.027 · 1.04 Impact Factor
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    ABSTRACT: In Venezuela, cucurbit viruses have been associated with important yield losses. Therefore, an extensive survey was conducted to determine the major cucurbit viruses in this country. Leaf samples from 284 cucurbit plants exhibiting virus-like symptoms were collected mainly in 2009–2010 from several states of Venezuela. They were assessed for viral infection by polymerase chain reaction (PCR) for Melon chlorotic mosaic virus (MeCMV) and reverse transcriptase (RT)-PCR for Papaya ringspot virus (PRSV), Zucchini yellow mosaic virus (ZYMV), Watermelon mosaic virus (WMV), Cucumber mosaic virus (CMV), Squash mosaic virus (SqMV) and Cucurbit aphid-borne yellows virus (CABYV). The most common virus in cucurbit fields, MeCMV, was present in 65·8% of samples. Its associated alphasatellite was found in 78% of samples positive for MeCMV. PRSV, ZYMV and WMV were found with different prevalence: 34·2, 32·4 and 1·1% respectively. CMV was also detected (6·7%) but SqMV and CABYV were not found. Single infections were more frequent than mixed infections (56·4 and 38·6%, respectively). For ZYMV, comparison and phylogenetic analyses of either polymerase and coat protein (NIb-CP) partial sequences or CP complete sequences revealed a low genetic diversity within Venezuelan isolates. Thirty-four ZYMV isolates were used for serological and biological analysis. Thirteen monoclonal antibodies showed a major group of isolates spread in several states and two groups located in Zulia only. Venezuelan ZYMV isolates showed biological variability on cucurbit cultivars susceptible, tolerant or resistant to ZYMV. Resistance to ZYMV in cucumber appears potentially durable, whereas resistance or tolerance in zucchini and melon may be easily overcome.
    Plant Pathology 02/2014; 63(1). DOI:10.1111/ppa.12072 · 2.12 Impact Factor
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    ABSTRACT: Zucchini yellow mosaic virus (ZYMV, genus Potyvirus) causes important crop losses in cucurbits worldwide. In France, ZYMV epidemics are sporadic but occasionally very severe. This contrasts with Watermelon mosaic virus (WMV, genus Potyvirus) which causes regular and early epidemics. Factors influencing ZYMV epidemiology are still poorly understood. In order to gain new insights on the ecology and epidemiology of this virus, a 5-year multilocation trial was conducted in which ZYMV spread and populations were studied in each of the 20 plot/year combinations and compared with WMV. Search for ZYMV alternative hosts was conducted by testing weeds growing naturally around one plot and also by checking ZYMV natural infections in selected ornamental species. Although similar ZYMV populations were observed occasionally in the same plot in two successive years suggesting the occurrence of overwintering hosts nearby, only two Lamium amplexicaule plants were found to be infected by ZYMV of 3459 weed samples that were tested. The scarcity of ZYMV reservoirs contrasts with the frequent detection of WMV in the same samples. Since ZYMV and WMV have many aphid vectors in common and are transmitted with similar efficiencies, the differences observed in ZYMV and WMV reservoir abundances could be a major explanatory factor for the differences observed in the typology of ZYMV and WMV epidemics in France. Other potential ZYMV alternative hosts have been identified in ornamental species including begonia. Although possible in a few cases, exchanges of populations between different plots located from 500m to 4km apart seem uncommon. Therefore, the potential dissemination range of ZYMV by its aphid vectors seems to be rather limited in a fragmented landscape.
    Virus Research 01/2014; 186. DOI:10.1016/j.virusres.2014.01.020 · 2.32 Impact Factor
  • Gustavo Romay · Herve Lecoq · Cecile Desbiez
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    ABSTRACT: Watermelon mosaic virus (WMV, Potyvirus) is an important virus of cucurbit crops worldwide, although it is rarely found in tropical regions. Cucumis anguria L. is a native species from tropical regions of Africa and can be found as a volunteer or cultivated plant in the Neotropic (1). In Venezuela, C. anguria is a ubiquitous volunteer cucurbit that grows in crop fields year round and may serve as reservoir for viruses. In 2009 and 2010, during surveys for viruses in cultivated and wild cucurbits, WMV was found at a low frequency (3 out of 284 samples) and two out of three positive samples were C. anguria. One of these samples was used to mechanically inoculate WMV to melon (Cucumis melo L.) and zucchini squash (Cucurbita pepo L.) plants. Typical symptoms of WMV were observed 2 weeks after inoculation and viral identification was confirmed by double antibody sandwich (DAS)-ELISA. Based on whole genome sequences, three phylogenetic groups of WMV, namely groups G1 to G3, are defined (2). Since molecular characterization of this virus is scarce in South America, the complete sequence of a WMV isolate recovered from C. anguria (hereafter, VE10-99) was obtained. RNA extractions, amplification procedures, and sequencing analyses were performed according to Desbiez and Lecoq (2). The total sequence length of VE10-99 isolate was 10,039 nucleotides, excluding the polyadenylated tail (GenBank Accession No. KC292915). This isolate had the typical potyviral genome organization, exhibiting a unique large ORF with 9 putative cleavage sites. In a BLAST analysis, the isolate most closely related to VE10-99 was the Chilean isolate CHI87-620 (EU660580), sharing 96% nucleotide identity. Phylogenetic analyses showed that VE10-99 belongs to group G2 of WMV. No evidence for recombination was found in the genome of VE10-99. Although recombination events have been noticed between members of G1 and G3, recombinant isolates between members of G2 and G1 are more frequent (2). In fact, the isolate CHI87-620 had been the only bona fide member of G2 until the sequencing of VE10-99. G2/G1 recombinants seem to have almost completely replaced the parental isolates throughout the world, probably due to a better fitness (2). To our knowledge, WMV natural infections in C. anguria had not been described before. The finding of a bona fide G2 member in Venezuela raises the question about the origin of G2 group. Currently, the prevalence of WMV appears reduced compared to the previous survey performed in Venezuela in 1966 (16 WMV-positive plants out of 95 samples) (3).
    Plant Disease 11/2013; 97(11):1515. DOI:10.1094/PDIS-02-13-0196-PDN · 3.02 Impact Factor
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    ABSTRACT: Here we develop a novel approach allowing the non-covalent assembly of proteins on well-defined nano-scaffolds such as virus particles. The antibody-binding peptide Z33 was genetically fused to the monomeric yellow fluorescent protein and 4-coumarate:CoA-ligase 2. This Z33 'tag' allowed their patterning on the surface of zucchini yellow mosaic virus by means of specific antibodies directed against the coat protein of the virus. The approach was validated by affinity assays and correlative microscopy. The coverage efficiency was about 87 %. Fluorescence and enzymatic activity were fully retained after assembly. The principle of using the combination of a scaffold-specific antibody and Z33-fusion proteins can be extended to a wide variety of proteins/enzymes and antigenic scaffolds to support coupling for creating functional 'biochips' with optical or catalytic properties.
    Biomacromolecules 11/2013; 14(12). DOI:10.1021/bm401291u · 5.75 Impact Factor
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    ABSTRACT: Although the biological variability of Watermelon mosaic virus is limited, isolates from the three main molecular groups differ in their ability to infect systemically Chenopodium quinoa. Mutations were introduced in a motif of three or five amino acids located in the N-terminal part of the coat protein, and differing in isolates from group 1 (motif: lysine-glutamic acid-alanine (Lys-Glu-Ala) or KEA, systemic on C. quinoa), group 2 (Lys-Glu-Thr or KET, not systemic on C. quinoa) and group 3 (KEKET, not systemic on C. quinoa). Mutagenesis of KEKET in an isolate from group 3 to KEA or KEKEA was sufficient to make the virus systemic on C. quinoa, whereas mutagenesis to KET had no effect. Introduction of a KEA motif in Zucchini yellow mosaic virus coat protein also resulted in systemic infection on C. quinoa. These mutations had no obvious effect on the disorder profile or potential post-translational modifications of the coat protein as determined in silico.
    Molecular Plant Pathology 08/2013; 15(2). DOI:10.1111/mpp.12076 · 4.72 Impact Factor
  • G Romay · H Lecoq · C Desbiez
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    ABSTRACT: In recent years, three new potyviruses have been described in the papaya ringspot virus (PRSV) cluster. In addition, two types of PRSV are recognized, type W, infecting cucurbit plants, and type P, infecting papaya and also cucurbits. A third type, PRSV-T, was also partially described in Guadeloupe. Complete genome sequencing of four PRSV-T isolates showed that this virus is a related virus that is distinct from PRSV, and the name zucchini tigré mosaic virus (ZTMV) is proposed, in reference to the typical symptoms observed in zucchini squash. Eleven other viral isolates from different geographic origins were confirmed as ZTMV isolates using the complete sequence of the cylindrical inclusion (CI) coding region, whereas pairwise sequence similarities in the coat protein (CP) coding region did not unambiguously distinguish ZTMV isolates from PRSV isolates. The use of the CI coding region for species demarcation appears more suitable than the CP coding region for closely related viruses. Principal coordinates analysis based on the biological behavior of the viral isolates studied clustered PRSV-P, PRSV-W and ZTMV isolates into three different groups. Therefore, ZTMV is different from PRSV in its molecular and biological properties.
    Archives of Virology 08/2013; 159(2). DOI:10.1007/s00705-013-1798-0 · 2.39 Impact Factor
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    ABSTRACT: Plant viruses are generally considered incapable of infecting vertebrates. Accordingly, they are not considered harmful for humans. However, a few studies questioned the certainty of this paradigm. Tobacco mosaic virus (TMV) RNA has been detected in human samples and TMV RNA translation has been described in animal cells. We sought to determine if TMV is detectable, persists, and remains viable in the lung tissues of mice following intratracheal inoculation, and we attempted to inoculate mouse macrophages with TMV. In the animal model, mice were intratracheally inoculated with 10(11) viral particles and were sacrificed at different time points. The virus was detected in the mouse lungs using immunohistochemistry, electron microscopy, real-time RT-PCR and sequencing, and its viability was studied with an infectivity assay on plants. In the cellular model, the culture medium of murine bone marrow derived macrophages (BMDM) was inoculated with different concentrations of TMV, and the virus was detected with real-time RT-PCR and immunofluorescence. In addition, anti-TMV antibodies were detected in mouse sera with ELISA. We showed that infectious TMV could enter and persist in mouse lungs via the intratracheal route. Over 14 days, the TMV RNA level decreased by 5 log(10) copies/ml in the mouse lungs and by 3.5 log(10) in macrophages recovered from bronchoalveolar lavage. TMV was localized to lung tissue, and its infectivity was observed on plants until 3 days after inoculation. In addition, anti-TMV antibody seroconversions were observed in the sera from mice 7 days after inoculation. In the cellular model, we observed that TMV persisted over 15 days after inoculation and it was visualized in the cytoplasm of the BMDM. This work shows that a plant virus, Tobacco mosaic virus, could persist and enter in cells in mammals, which raises questions about the potential interactions between TMV and human hosts.
    PLoS ONE 01/2013; 8(1):e54993. DOI:10.1371/journal.pone.0054993 · 3.23 Impact Factor
  • Hervé Lecoq · Cécile Desbiez
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    ABSTRACT: Cucurbit crops may be affected by at least 28 different viruses in the Mediterranean basin. Some of these viruses are widely distributed and cause severe yield losses while others are restricted to limited areas or specific crops, and have only a negligible economic impact. A striking feature of cucurbit viruses in the Mediterranean basin is their always increasing diversity. Indeed, new viruses are regularly isolated and over the past 35 years one "new" cucurbit virus has been reported on average every 2 years. Among these "new" viruses some were already reported in other parts of the world, but others such as Zucchini yellow mosaic virus (ZYMV), one of the most severe cucurbit viruses and Cucurbit aphid-borne yellows virus (CABYV), one of the most prevalent cucurbit viruses, were first described in the Mediterranean area. Why this region may be a potential "hot-spot" for cucurbit virus diversity is not fully known. This could be related to the diversity of cropping practices, of cultivar types but also to the important commercial exchanges that always prevailed in this part of the world. This chapter describes the major cucurbit viruses occurring in the Mediterranean basin, discusses factors involved in their emergence and presents options for developing sustainable control strategies.
    Advances in Virus Research 06/2012; 84:67-126. DOI:10.1016/B978-0-12-394314-9.00003-8 · 4.57 Impact Factor
  • C Desbiez · C Chandeysson · H Lecoq · B Moury
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    ABSTRACT: The availability of an infectious cDNA clone is a prerequisite for genetic studies on RNA viruses. However, despite important improvement in molecular biology techniques during the last decades, obtaining such clones often remains tedious, time-consuming and rather unpredictable. In the case of potyviruses, cDNA clones are frequently unstable due to the toxicity of some viral proteins for bacteria. The problem can be overcome by inserting introns into the viral sequence but this requires additional steps in the cloning process and depends on the availability of suitable restriction sites in the viral sequence or adjunction of such sites by mutagenesis. Homologous recombination in yeast rather than in vitro restriction and ligation can be used to build infectious clones or other viral constructs. This paper describes how, by using recombination in yeast and fusion PCR, infectious intron-containing clones were obtained within a few weeks for two strains of watermelon mosaic virus (WMV, Potyvirus), whereas previous attempts using "classical" cloning techniques had failed repeatedly. Using the same approach, intronless infectious clones of two other potyviruses, zucchini yellow mosaic virus (ZYMV) and papaya ringspot virus (PRSV), were obtained in less than two weeks.
    Journal of virological methods 04/2012; 183(1):94-7. DOI:10.1016/j.jviromet.2012.03.035 · 1.78 Impact Factor
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    ABSTRACT: Aphis gossypii is a major pest of Cucurbitaceae crops as much by causing primary damages (sap uptake) as by being an important vector of viruses. The Vat gene confers to the melon a resistance to the colonization by A. gossypii as well as a resistance to the not persistent viruses (CMV, WMV,..) transmitted by these aphids. It is however ineffective to block the transmission of the viruses carried by other aphid species. The use of Vat is thus generally coupled with aphicid treatments to limit the viral transmission by the not colonizing aphids. However, the progressive reduction of the usage of the phytosanitary products in the crop protection imposed by the evolution of the regulation (plan Ecophyto 2018) leads to look for new strategies integrating cultural practices and genetics for the management of the bioagressors. The bibliography suggests that the management of field margins (strips sown with non host grass or flower mixtures) could be an effective option to decrease 1) the aphid pressure (and thus the risk of bypassing Vat) by favoring the development of natural enemies and 2) the virus pressure by constituting a filter reducing the viral load of aphids before they reach the crop. The hypothesis tested in this project is that an adequate manipulation of the environment of the crop can contribute to regulate the populations of aphids and\or their viral load and therefore to reduce the risk of viral epidemics. The effect of three types of field margins (naked soil, grassy strips and flower strips) is evaluated on the efficiency of the Vat-mediated resistance.
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    ABSTRACT: Watermelon mosaic virus (WMV, genus Potyvirus, family Potyviridae) was reported for the first time in France in 1974, and it is now the most prevalent virus in cucurbit crops. In 2000, new strains referred as 'emerging' (EM) strains were detected in South-eastern France. EM strains are generally more severe and phylogenetically distinct from those previously reported in this country and referred as 'classic' (CL) strains. Since 2000, EM strains have been progressively replacing CL strains in several areas where they co-exist. In order to explain this rapid shift in virus populations, the biological properties of a set of 17 CL and EM WMV isolates were compared. No major differences were observed when comparing a limited host range including 48 different plant species or cultivars. Only two species were differential; Chenopodium quinoa was systemically infected by CL and not by EM isolates whereas Ranunculus sardous was systemically infected by EM and not by CL isolates. A considerable variability was observed in aphid transmission efficiencies but this could not be correlated to the CL or EM types. Two subsets of five isolates of each group were used to compare aphid transmission efficiencies from single and double (CL-EM) infections using six different cucurbit and non-cucurbit hosts. EM isolates were generally better transmitted from mixed CL-EM infections than CL isolates and CL transmission rates were significantly lower from double than from single infections. Cross-protection was only partial between CL and EM strains leading to frequent double infections, and only a slight asymmetry was observed in cross-protection efficiencies. Since double infections occur very commonly in fields, the preferential transmission of EM from mixed CL-EM infections could be one of the factors leading to the displacement of CL isolates by EM isolates.
    Virus Research 05/2011; 159(2):115-23. DOI:10.1016/j.virusres.2011.05.004 · 2.32 Impact Factor
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    ABSTRACT: Since their introduction in south-eastern France around 1999, new, 'emerging' (EM) strains of watermelon mosaic virus (WMV) coexist with the 'classic' (CL) strains present for more than 40 years. This situation constitutes a unique opportunity to estimate the frequency of recombinants appearing in the few years following introduction of new strains of a plant RNA virus. Molecular analyses performed on more than 1000 isolates from epidemiological surveys (2004-2008) and from experimental plots (2009-2010), and targeting only recombinants that became predominant in at least one plant, revealed at least seven independent CL/EM or EM/EM recombination events. The frequency of recombinants involving at least one EM parent in the natural populations tested was on the order of 1 %. No new recombinant was detected for more than 1 year, and none but one in more than one location. In tests comparing host range and aphid transmissibility, the new recombinants did not display a better fitness than their 'parental' isolates. No recombinant was detected from artificial mixed infections of CL and EM isolates of various hosts after testing more than 1500 subcultures obtained after single-aphid transmission. These results constitute one of the first estimations of the frequency of recombinants in natural conditions for a plant RNA virus. This suggests that although viable recombinants of WMV are not rare, and although recombination may potentially lead to new highly damaging strains, the new recombinants observed so far had a lower fitness than the parental strains and did not emerge durably in the populations.
    Journal of General Virology 04/2011; 92(Pt 8):1939-48. DOI:10.1099/vir.0.031401-0 · 3.18 Impact Factor
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    C Desbiez · B Moury · H Lecoq
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    ABSTRACT: All viruses are obligatory parasites that must develop tight interactions with their hosts to complete their infectious cycle. Viruses infecting plants share many structural and functional similarities with those infecting other organisms, particularly animals and fungi. Quantitative data regarding their evolutionary mechanisms--generation of variability by mutation and recombination, changes in populations by selection and genetic drift have been obtained only recently, and appear rather similar to those measured for animal viruses.This review presents an update of our knowledge of the phylogenetic and evolutionary characteristics of plant viruses and their relation to their plant hosts, in comparison with viruses infecting other organisms.
    Infection, genetics and evolution: journal of molecular epidemiology and evolutionary genetics in infectious diseases 03/2011; 11(5):812-24. DOI:10.1016/j.meegid.2011.02.020 · 3.02 Impact Factor
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    ABSTRACT: A virus isolate (Su-95-67) was obtained from a snake melon (Cucumis melo var. flexuosus) plant presenting severe chlorotic spots, mosaic, stunting, and leaf deformations collected in Eastern Sudan in 1995. Su-95-67 was easily mechanically transmissible and had a host range limited to a few cucurbit species. Isometric virus particles approximately 30 nm in diameter were observed in leaf dip preparations. A cytopathological study did not reveal alterations specific for a virus genus or family. A polyclonal antiserum was obtained and used in double-antibody sandwich enzyme-linked immunosorbent assay (DAS-ELISA). Su-95-67 was transmitted by seed at a low rate, by the red melon beetle (Aulacophora foveicollis), but not by the melon aphid (Aphis gossypii). Because Su-95-67 shared several properties with sobemoviruses, generic Sobemovirus reverse-transcription polymerase chain reaction primers were developed. They allowed amplification of a 384-bp fragment from extracts of plants infected by two sobemoviruses or by Su-95-67 but not from healthy plants extracts. Sequence comparison confirmed that Su-95-67 belongs to a new tentative Sobemovirus species for which we propose the name Snake melon asteroid mosaic virus (SMAMV). DAS-ELISA tests conducted on extracts of virus-infected cucurbit plants collected from 1992 to 2003 revealed the presence of SMAMV in 10.2% of 600 samples originating from different regions of Sudan.
    Plant Disease 02/2011; 95(2):153-157. DOI:10.1094/PDIS-06-10-0447 · 3.02 Impact Factor
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    ABSTRACT: We present here the first comprehensive genetic characterization of melon landraces from the humid tropics of southern India. The genetic diversity among 50 melon landraces collected from 3 agro-ecological regions of southern India (6 agro-ecological sub-regions) was assessed by variation at 17 SSR loci, morphological traits of plant habit and fruit, 2 yield-associated traits, pest and disease resistance, biochemical composition (ascorbic acid, carotenoids, titrable acidity) and mineral content (P, K, Fe, Zn). Differences among accessions were observed in plant and fruit traits. Melon germplasm with high titrable acidity, higher than average amounts of mineral content and resistance to Cucumber mosaic virus, Zucchini yellow mosaic virus, powdery mildew (races 1, 2, 3, 5), Fusarium wilt (races 1, 2), Aphis gossypii and leafminer was recorded in the collection. A high level of genetic variability in melon germplasm was suggested by the SSR analysis. Comparative analysis using SSRs of the genetic variability between Indian melons from north, south, and east regions and reference accessions of melon from Spain, France, Japan, Korea, Iraq, Zambia showed regional differentiation between Indian melon accessions and that Indian germplasm was weakly related to the melon accessions from other parts of the world, suggesting that an important portion of the genetic variability found within this melon collection has not been used yet for the development of new cultivars. Additional collections of acidulus melon germplasm should be made in southern India and adequate management of this important genetic resource is clearly a necessity. Keywords Cucumis melo –Fungi–Genetic variation–Insect–Landraces–Microsatellite–Resistance–Taxonomic relationships–Virus
    Genetic Resources and Crop Evolution 02/2011; 58(2):225-243. DOI:10.1007/s10722-010-9564-6 · 1.46 Impact Factor
  • Plant Disease 11/2010; 94(11):1378-1378. DOI:10.1094/PDIS-06-10-0416 · 3.02 Impact Factor

Publication Stats

2k Citations
205.27 Total Impact Points


  • 1994–2013
    • French National Institute for Agricultural Research
      • Pathologie Végétale
      Lutetia Parisorum, Île-de-France, France
  • 1992
    • University of California, Davis
      • Department of Plant Pathology
      Davis, California, United States