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Claude Bragard - One of the best experts on this subject based on the ideXlab platform.

  • Chapter 9 : Beet necrotic yellow vein virus and other soil-borne viruses in sugar Beet
    2008
    Co-Authors: Claude Bragard, Alexandre Meunier
    Abstract:

    The worldwide extension of the rhizomania disease is one of the most worrying constraints that have to be faced by the sugar Beet crop for the past 20 to 30 years. The disease is caused by the Beet necrotic yellow vein virus, a Benyvirus. The virus affects both the quantity and the quality of the production. But the major problem is probably lying in the long-term survival of the virus associated to its vector, Polymyxa betae, a soil-inhabiting plasmodiophoromycete. This vetor has been also shown to transmit other viruses to sugar Beet, like the Benyvirus, Beet soil-borne mosaic virus or the Pomovirus like the Beet soil-borne virus and the Beet virus Q. Control of rhizomania depends on the accurate and sensitive detection of BNYVV in plants and soil, for a precocious of infected fields and for breeding resistant sugar Beet lines. Also, the complexity introduced by the co-occurrence with other soil-inhabiting viruses raises needs for efficient detection techniques. Therefore, molecular diagnostic methods have been thoroughly used and developed for the identification and quantification of the Beet necrotic yellow vein virus as well as the other soil-borne sugar Beet viruses and their vector. A description of sugar Beet soil-borne viruses and their vector Polymyxa betae is therefore discussed in this chapter, focusing on the molecular diagnostic methods proposed for their detection and quantification, from serological to the polymerase-based methods.

  • Beet necrotic yellow vein virus and other soil-borne viruses in sugar Beet
    2006
    Co-Authors: Claude Bragard, Alexandre Meunier
    Abstract:

    The worldwide extension of the rhizomania disease is one of the most worrying constraints that have to be faced by the sugar Beet crop for the past 20 to 30 years.The disease is caused by the Beet necrotic yellow vein virus, a Benyvirus. The virus affects both the quantity and the quality of the production. But the major problem is probably lying in the long-term survival of the virus associated to its vector, Polymyxa betae, a soil-inhabiting plasmodiophoromycete. This vector has been also shown to transmit other viruses to sugar Beet, like the Benyvirus, Beet soil-borne mosaic virus or the Pomovirus like the Beet soil-borne virus and the Beet virus Q. Control of rhizomania depends on the accurate and sensitive detection of BNYVV in plants and soil, for a precocious of infected fields and for breeding resistant sugar Beet lines. Also, the complexity introduced by the co-occurrence with other soil-inhibating viruses raises needs for efficient detection techniques. Therefore, molecular diagnostic methods have been thoroughly used and developed for the identification and quantification of the Beet necrotic yellow vein virus as well as the other soil-borne sugar Beet viruses and their vector. A description of sugar Beet soil-borne viruses and their vector Polymyxa betae is therefore discussed in this chapter, focusing on the molecular diagnostic methods proposed for their detection and quantification, from serological to the polymerase-based methods.

  • multiplex reverse transcription pcr for simultaneous detection of Beet necrotic yellow vein virus Beet soilborne virus and Beet virus q and their vector polymyxa betae keskin on sugar Beet
    Applied and Environmental Microbiology, 2003
    Co-Authors: Alexandre Meunier, Jeanfrancois Schmit, Arnaud Stas, Nazli Kutluk, Claude Bragard
    Abstract:

    Three soilborne viruses transmitted by Polymyxa betae KESKIN in sugar Beet have been described: Beet necrotic yellow vein virus (BNYVV), the agent of rhizomania, Beet soilborne virus (BSBV), and Beet virus Q (BVQ). A multiplex reverse transcription-PCR technique was developed to simultaneously detect BNYVV, BSBV, and BVQ, together with their vector, P. betae. The detection threshold of the test was up to 128 times greater than that of an enzyme-linked immunosorbent assay. Systematic association of BNYVV with one or two different pomoviruses was observed. BVQ was detected in samples from Belgium, Bulgaria, France, Germany, Hungary, Italy, Sweden, and The Netherlands but not in samples from Turkey.

  • Multiplex Reverse Transcription-PCR for Simultaneous Detection of Beet Necrotic Yellow Vein Virus, Beet Soilborne Virus, and Beet Virus Q and Their Vector Polymyxa betae KESKIN on Sugar Beet
    Applied and Environmental Microbiology, 2003
    Co-Authors: Alexandre Meunier, Jeanfrancois Schmit, Arnaud Stas, Nazli Kutluk, Claude Bragard
    Abstract:

    Three soilborne viruses transmitted by Polymyxa betae KESKIN in sugar Beet have been described: Beet necrotic yellow vein virus (BNYVV), the agent of rhizomania, Beet soilborne virus (BSBV), and Beet virus Q (BVQ). A multiplex reverse transcription-PCR technique was developed to simultaneously detect BNYVV, BSBV, and BVQ, together with their vector, P. betae. The detection threshold of the test was up to 128 times greater than that of an enzyme-linked immunosorbent assay. Systematic association of BNYVV with one or two different pomoviruses was observed. BVQ was detected in samples from Belgium, Bulgaria, France, Germany, Hungary, Italy, Sweden, and The Netherlands but not in samples from Turkey.

Nathalie Colbach - One of the best experts on this subject based on the ideXlab platform.

  • Contribution of groundkeepers vs. weed Beet to gene escape from sugar Beet (Beta vulgaris spp.). Consequences for growing genetically-modified sugar Beet - A modelling approach
    Field Crops Research, 2012
    Co-Authors: Mathilde Sester, Henri Darmency, Nathalie Colbach
    Abstract:

    Weed Beet cannot be controlled by herbicides in sugar Beet (except via height-selective applicators) as it is a crop relative, descending from accidentally flowering sugar Beet (Beta vulgaris) crop plants either because of vernalization during cold springs, or presence of a dominant bolting allele in sugar Beet seed lots due to cross-pollination by annual wild Beet (B. vulgaris ssp. maritima) in seed production areas. A second, minor source of weed Beet are crop roots lost during harvest. These roots ("groundkeepers") can reproduce in the year after sugar Beet and potentially contribute to weed Beet dynamics and gene flow. Bolting, flowering and seed production timing and potential of groundkeepers were measured in field experiments. Bolting and flowering were faster in groundkeepers vs. weed Beet; flower and seed production was lower in groundkeepers but the latter were less sensitive to competitive crops. The measured parameters were used to introduce a ground-keeper life-cycle into the GENESYS-Beet model which quantifies the effects of cropping systems on weed Beet in landscapes. Simulations over several years showed weed Beet dynamics to be more sensitive to groundkeeper parameter values than to root loss at sugar Beet harvest. Groundkeepers were identified as a key source of weed Beet populations and of gene escape from novel sugar Beet varieties (e.g. genetically-modified herbicide-tolerant varieties) in the absence of crop bolters. The control of the latter, either by manual weeding or by genetic improvement of sugar Beet varieties, was shown to be essential for controlling weed Beet populations and avoid the advent of herbicide-tolerant weed Beet

  • Identifying key components of weed Beet management using sensitivity analyses of the GeneSys‐Beet model in GM sugar Beet
    Weed Research, 2009
    Co-Authors: Yann Tricault, H. Darmency, Nathalie Colbach
    Abstract:

    Summary Genetically-modified (GM) sugar Beet varieties tolerant to non-selective herbicides would be useful for managing weed Beet, an annual form of Beta vulgaris impossible to eliminate with herbicides in sugar Beet. However, it is highly probable that the herbicide-tolerance transgene would be transmitted to the weed through pollen flow. It is therefore essential to study how weed Beet. particularly Herbicide-Tolerant (HT) populations, develop in cropping systems and how to optimise crop succession and management for controlling these weeds. As multiple interactions and long-term effects make field experiments impractical, we carried out a simulation study with a deterministic and mechanistic model, GeneSys-Beet, which quantifies weed Beet dynamics and gene flow in cropping systems with interactions with climate, soil structure and hydro-thermal conditions. The sensitivity analysis consisted of 250 000 random combinations of input variables to rank cropping system components according to their effect on both total and GM weed Beet infestations. Frequency of sugar Beet crops, crop succession, manual and mechanical weeding and tillage were identified as the most important variables. Several cultivation techniques must be combined to efficiently control weed Beet. Our recommendations are complex, but a delayed return of sugar Beet in the rotation. Harvest should be followed as soon as possible by a shallow tilling; tillage should always be as shallow and as early as possible, except before sugar Beet where mouldboard ploughing is advisable. If possible, sowing dates should be delayed. Sugar Beet should be weeded mechanically and/or manually, aiming at late and efficient, rather than early or frequent operations. Herbicides should be applied whenever possible and target all weed Beet stages and genotypes. Set-aside must be cut as frequently and as late as possible.

  • Identifying key components of weed Beet management using sensitivity analyses of the GeneSys-Beet model in GM sugar Beet
    Weed Research, 2009
    Co-Authors: Yann Tricault, H. Darmency, Nathalie Colbach
    Abstract:

    P>Genetically-modified (GM) sugar Beet varieties tolerant to non-selective herbicides would be useful for managing weed Beet, an annual form of Beta vulgaris impossible to eliminate with herbicides in sugar Beet. However, it is highly probable that the he

  • GeneSys-Beet: A model of the effects of cropping systems on gene flow between sugar Beet and weed Beet
    Field Crops Research, 2008
    Co-Authors: Mathilde Sester, Henri Darmency, Yann Tricault, Nathalie Colbach
    Abstract:

    Abstract A weedy form of the genus Beta , i.e. Beta vulgaris ssp. vulgaris (hence “weed Beet”) frequently found in sugar Beet is impossible to eliminate with herbicides because of its genetic proximity to the crop. It is presumed to be the progeny of accidental hybrids between sugar Beet (ssp. vulgari s) and wild Beet (ssp. maritima ), or of sugar Beet varieties sensitive to vernalization and sown early in years with late cold spells. In this context, genetically modified (GM) sugar Beet varieties tolerant to non-selective herbicides would be interesting to manage weed Beet. However, because of the proximity of the weed to the crop, it is highly probable that the herbicide-tolerance transgene would be transmitted to the weed. To evaluate the likelihood of gene flow from GM varieties to weed Beet and to propose cropping systems that reduce this likelihood, a model of the effects of cropping systems on population dynamics and gene flow in weed Beet was developed, based on the existing spatio-temporal framework GENESYS and on field experiments for parametrising the life-cycle of weed Beet. The resulting GENESYS-Beet model consists in simulating every year the life-cycle of weed and crop Beet in each field of a given region. During flowering, the various life-cycles connect, leading to pollen exchanges which depend on field areas, shapes and distances. The life-cycle consists of a succession of life-stages for which both densities and genotype proportions are calculated. The relationships between the various stages depend on the crop grown in the field, the stage and genotype of the modelled crop relative, as well as the cultivation techniques (tillage tools and dates, sowing date and density, herbicides, mechanical and manual weeding, harvest date) used to manage the crop. Simulations of GM spread in different farms and regions and of the effects of weed management on the advent of GM Beet were carried out to illustrate the possible uses of the model and the consequences of co-existing GM and non-GM crops.

  • GeneSys-Beet: A model of the effects of cropping systems on gene flow between sugar Beet and weed Beet
    Field Crops Research, 2008
    Co-Authors: M. Sester, Yann Tricault, H. Darmency, Nathalie Colbach
    Abstract:

    A weedy form of the genus Beta, i.e. Beta vulgaris ssp. vulgaris (hence ''weed Beet'') frequently found in sugar Beet is impossible to eliminate with herbicides because of its genetic proximity to the crop. It is presumed to be the progeny of accidental hybrids between sugar Beet (ssp. vulgaris) and wild Beet (ssp. maritima), or of sugar Beet varieties sensitive to vernalization and sown early in years with late cold spells. In this context, genetically modified (GM) sugar Beet varieties tolerant to non-selective herbicides would be interesting to manage weed Beet. However, because of the proximity of the weed to the crop, it is highly probable that the herbicide-tolerance transgene would be transmitted to the weed. To evaluate the likelihood of gene flow from GM varieties to weed Beet and to propose cropping systems that reduce this likelihood, a model of the effects of cropping systems on population dynamics and gene flow in weed Beet was developed, based on the existing spatio-temporal framework GENESYS and on field experiments for parametrising the life-cycle of weed Beet. The resulting GENESYS-Beet model consists in simulating every year the life-cycle of weed and crop Beet in each field of a given region. During flowering, the various life-cycles connect, leading to pollen exchanges which depend on field areas, shapes and distances. The life-cycle consists of a succession of life-stages for which both densities and genotype proportions are calculated. The relationships between the various stages depend on the crop grown in the field, the stage and genotype of the modelled crop relative, as well as the cultivation techniques (tillage tools and dates, sowing date and density, herbicides,mechanical and manual weeding, harvest date) used to manage the crop. Simulations of GM spread in different farms and regions and of the effects of weed management on the advent of GM Beet were carried out to illustrate the possible uses of the model and the consequences of co-existing GM and non-GM crops. (Résumé d'auteur)

Alexandre Meunier - One of the best experts on this subject based on the ideXlab platform.

  • Chapter 9 : Beet necrotic yellow vein virus and other soil-borne viruses in sugar Beet
    2008
    Co-Authors: Claude Bragard, Alexandre Meunier
    Abstract:

    The worldwide extension of the rhizomania disease is one of the most worrying constraints that have to be faced by the sugar Beet crop for the past 20 to 30 years. The disease is caused by the Beet necrotic yellow vein virus, a Benyvirus. The virus affects both the quantity and the quality of the production. But the major problem is probably lying in the long-term survival of the virus associated to its vector, Polymyxa betae, a soil-inhabiting plasmodiophoromycete. This vetor has been also shown to transmit other viruses to sugar Beet, like the Benyvirus, Beet soil-borne mosaic virus or the Pomovirus like the Beet soil-borne virus and the Beet virus Q. Control of rhizomania depends on the accurate and sensitive detection of BNYVV in plants and soil, for a precocious of infected fields and for breeding resistant sugar Beet lines. Also, the complexity introduced by the co-occurrence with other soil-inhabiting viruses raises needs for efficient detection techniques. Therefore, molecular diagnostic methods have been thoroughly used and developed for the identification and quantification of the Beet necrotic yellow vein virus as well as the other soil-borne sugar Beet viruses and their vector. A description of sugar Beet soil-borne viruses and their vector Polymyxa betae is therefore discussed in this chapter, focusing on the molecular diagnostic methods proposed for their detection and quantification, from serological to the polymerase-based methods.

  • Beet necrotic yellow vein virus and other soil-borne viruses in sugar Beet
    2006
    Co-Authors: Claude Bragard, Alexandre Meunier
    Abstract:

    The worldwide extension of the rhizomania disease is one of the most worrying constraints that have to be faced by the sugar Beet crop for the past 20 to 30 years.The disease is caused by the Beet necrotic yellow vein virus, a Benyvirus. The virus affects both the quantity and the quality of the production. But the major problem is probably lying in the long-term survival of the virus associated to its vector, Polymyxa betae, a soil-inhabiting plasmodiophoromycete. This vector has been also shown to transmit other viruses to sugar Beet, like the Benyvirus, Beet soil-borne mosaic virus or the Pomovirus like the Beet soil-borne virus and the Beet virus Q. Control of rhizomania depends on the accurate and sensitive detection of BNYVV in plants and soil, for a precocious of infected fields and for breeding resistant sugar Beet lines. Also, the complexity introduced by the co-occurrence with other soil-inhibating viruses raises needs for efficient detection techniques. Therefore, molecular diagnostic methods have been thoroughly used and developed for the identification and quantification of the Beet necrotic yellow vein virus as well as the other soil-borne sugar Beet viruses and their vector. A description of sugar Beet soil-borne viruses and their vector Polymyxa betae is therefore discussed in this chapter, focusing on the molecular diagnostic methods proposed for their detection and quantification, from serological to the polymerase-based methods.

  • multiplex reverse transcription pcr for simultaneous detection of Beet necrotic yellow vein virus Beet soilborne virus and Beet virus q and their vector polymyxa betae keskin on sugar Beet
    Applied and Environmental Microbiology, 2003
    Co-Authors: Alexandre Meunier, Jeanfrancois Schmit, Arnaud Stas, Nazli Kutluk, Claude Bragard
    Abstract:

    Three soilborne viruses transmitted by Polymyxa betae KESKIN in sugar Beet have been described: Beet necrotic yellow vein virus (BNYVV), the agent of rhizomania, Beet soilborne virus (BSBV), and Beet virus Q (BVQ). A multiplex reverse transcription-PCR technique was developed to simultaneously detect BNYVV, BSBV, and BVQ, together with their vector, P. betae. The detection threshold of the test was up to 128 times greater than that of an enzyme-linked immunosorbent assay. Systematic association of BNYVV with one or two different pomoviruses was observed. BVQ was detected in samples from Belgium, Bulgaria, France, Germany, Hungary, Italy, Sweden, and The Netherlands but not in samples from Turkey.

  • Multiplex Reverse Transcription-PCR for Simultaneous Detection of Beet Necrotic Yellow Vein Virus, Beet Soilborne Virus, and Beet Virus Q and Their Vector Polymyxa betae KESKIN on Sugar Beet
    Applied and Environmental Microbiology, 2003
    Co-Authors: Alexandre Meunier, Jeanfrancois Schmit, Arnaud Stas, Nazli Kutluk, Claude Bragard
    Abstract:

    Three soilborne viruses transmitted by Polymyxa betae KESKIN in sugar Beet have been described: Beet necrotic yellow vein virus (BNYVV), the agent of rhizomania, Beet soilborne virus (BSBV), and Beet virus Q (BVQ). A multiplex reverse transcription-PCR technique was developed to simultaneously detect BNYVV, BSBV, and BVQ, together with their vector, P. betae. The detection threshold of the test was up to 128 times greater than that of an enzyme-linked immunosorbent assay. Systematic association of BNYVV with one or two different pomoviruses was observed. BVQ was detected in samples from Belgium, Bulgaria, France, Germany, Hungary, Italy, Sweden, and The Netherlands but not in samples from Turkey.

Olivier Lemaire - One of the best experts on this subject based on the ideXlab platform.

  • Biological and molecular characterization of an american sugar Beet-infecting Beet western yellows virus isolate
    Plant Disease, 2008
    Co-Authors: Monique Beuve, Mark Stevens, Hsing-yeh Liu, William M. Winntermantel, Sébastien Hauser, Olivier Lemaire
    Abstract:

    Three aphid-transmitted viruses belonging to the Polerovirus genus, Beet mild yellowing virus (BMYV), Beet chlorosis virus (BChV), and Beet western yellows virus (BWYV), have been described as pathogens of sugar Beet. We present the complete biological, serological, and molecular characterization of an American isolate of Beet western yellows virus (BWYV-USA), collected from yellow Beet leaves. The biological data suggested that BWYV-USA displayed a host range similar to that of BMYV, but distinct from those of BChV and the lettuce and rape isolates of Turnip yellows virus. The complete genomic RNA sequence of BWYV-USA showed a genetic organization and expression typical of other Polerovirus members. Comparisons of deduced amino acid sequences showed that P0 and the putative replicase complex (P1-P2) of BWYV-USA are more closely related to Cucurbit aphid-borne yellows virus (CABYV) than to BMYV, whereas alignments of P3, P4, and P5 showed the highest homology with BMYV. Intraspecific and interspecific phylogenetic analyses have suggested that the BWYV-USA genome may be the result of recombination events between a CABYV-like ancestor contributing open reading frame (ORF) 0, ORF 1, and ORF 2, and a Beet Polerovirus progenitor providing the 3' ORFs, with a similar mechanism of speciation occurring for BMYV in Europe. Results demonstrate that BWYV-USA is a distinct species in the Polerovirus genus, clarifying the nomenclature of this important group of viruses.

Jeanfrancois Schmit - One of the best experts on this subject based on the ideXlab platform.