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Primitivo Caballero - One of the best experts on this subject based on the ideXlab platform.

  • remarkably efficient production of a highly insecticidal Chrysodeixis chalcites nucleopolyhedrovirus chchnpv isolate in its homologous host
    Pest Management Science, 2018
    Co-Authors: Alexandra Bernal, Oihane Simón, Trevor Williams, Primitivo Caballero, Delia Muñoz
    Abstract:

    Background A Chrysodeixis chalcites nucleopolyhedrovirus from the Canary Islands (ChchNPV-TF1) has proved to be effective for control of Chrysodeixis chalcites on banana crops. Commercialization of this virus as a bioinsecticide requires an efficient production system. Results The sixth instar (L6 ) was the most suitable for virus production, producing 1.80 × 1011 occlusion bodies (OB)/larva and showed a lower prevalence of cannibalism (5.4%) than fourth (L4 ) or fifth (L5 ) instars. Inoculation of L6 at 24 h post molting produced six times more OB (5.72 × 1011 OB/larva) than recently molted L6 larvae (1.00 × 1011 OB/larva). No significant differences were recorded in mean time to death (165-175 h) or OB production per larva (3.75 × 1011 to 5.97 × 1011 ) or per mg larval weight (1.30 × 1011 to 2.11 × 109 ), in larvae inoculated with a range of inoculum concentrations (LC50 -LC90 ). Groups of infected L6 larvae reared at a density of 150 larvae/container produced a greater total number of OBs (8.07 × 1013 OB/container) than lower densities (25, 50 and 100 OB/container), and a similar number to containers with 200 inoculated larvae (8.43 × 1013 OB/container). Conclusion The processes described here allow efficient production of sufficient OBs to treat ∼ 40 ha of banana crops using the insects from a single container. © 2018 Society of Chemical Industry.

  • Chrysodeixis chalcites nucleopolyhedrovirus chchnpv natural occurrence and efficacy as a biological insecticide on young banana plants in greenhouse and open field conditions on the canary islands
    PLOS ONE, 2017
    Co-Authors: Ernesto Gabriel Fuentes, Oihane Simón, Trevor Williams, Primitivo Caballero, Estrella Hernandezsuarez
    Abstract:

    Chrysodeixis chalcites, an important pest of banana crops on the Canary Islands, is usually controlled by chemical insecticides. The present study aimed to evaluate the efficacy of the most prevalent isolate of the Chrysodeixis chalcites nucleopolyhedrovirus (ChchNPV, Baculoviridae) as a biological insecticide. Overall the prevalence of ChchNPV infection in C. chalcites populations was 2.3% (103 infected larvae out of 4,438 sampled), but varied from 0–4.8% on Tenerife and was usually low (0–2%) on the other islands. On Tenerife, infected larvae were present at 11 out of 17 plantations sampled. The prevalence of infection in larvae on bananas grown under greenhouse structures was significantly higher (3%) than in open-field sites (1.4%). The ChchNPV-TF1 isolate was the most abundant and widespread of four genetic variants of the virus. Application of 1.0x109 viral occlusion bodies (OBs)/l of ChchNPV-TF1 significantly reduced C. chalcites foliar damage in young banana plants as did commonly used pesticides, both in greenhouse and open-field sites. The insecticidal efficacy of ChchNPV-TF1 was similar to that of indoxacarb and a Bacillus thuringiensis (Bt)-based insecticide in one year of trials and similar to Bt in the following year of trails in greenhouse and field crops. However, larvae collected at different time intervals following virus treatments and reared in the laboratory experienced 2–7 fold more mortality than insects from conventional insecticide treatments. This suggests that the acquisition of lethal dose occurred over an extended period (up to 7 days) compared to a brief peak in larvae on plants treated with conventional insecticides. These results should prove useful for the registration of a ChchNPV-based insecticide for integrated management of this pest in banana crops on the Canary Islands.

  • Restriction endonuclease analysis of LaolNPV DNA.
    2017
    Co-Authors: Oihane Simón, Martin A. Erlandson, Marie Frayssinet, Trevor Williams, David A. Theilmann, Anne-nathalie Volkoff, Primitivo Caballero
    Abstract:

    Restriction endonuclease profiles following digestion of A) genomic DNAs of the seven isolates of LaolNPV collected in alfalfa crops nearby Montpellier with BglII, EcoRI and PstI enzymes, B) genomic DNAs of Chrysodeixis chalcites NPV (Chch), Helicoverpa armigera SNPV (Hear), Spodoptera littoralis (Spli), Spodopera exigua MNPV (Se) and the virus under study (LaolNPV) with BamHI, BglII, EcoRI and PstI, and C) genomic DNAs of Mamestra brassicae MNPV (Mb), Mamestra configurata NPV-A (MacoA), Mamestra configurata NPV-B (MacoB) and LaolNPV with BglII, EcoRI and PstI.

  • Efficacy of an alphabaculovirus-based biological insecticide for control of Chrysodeixis chalcites (Lepidoptera: Noctuidae) on tomato and banana crops.
    Pest management science, 2015
    Co-Authors: Oihane Simón, Trevor Williams, Alexandra Bernal, Aurelio Carnero, Estrella Hernández-suárez, Delia Muñoz, Primitivo Caballero
    Abstract:

    BACKGROUND Chrysodeixis chalcites (Esper) is a major pest of tomato in Mediterranean countries and attacks banana in the Canary Islands (Spain). The efficacy of Chrysodeixis chalcites single nucleopolyhedrovirus (ChchSNPV-TF1) was evaluated in plant growth chambers and greenhouse trials performed on tomato and banana plants respectively. Treatments were applied using a compressed air sprayer. RESULTS Mean (± SE) lethal infection varied from 77 ± 10% to 94 ± 3% in second-instar larvae fed for 2 days on tomato plants treated with 2 × 106 to 5 × 107 virus occlusion bodies (OBs) L−1, increasing to ∼100% infection after 7 days. Mortality of larvae collected from banana at different intervals post-application varied from 54 ± 10% to 96 ± 4% in treatments involving 1 × 108–1 × 109 OBs L−1, whereas indoxacarb (Steward 30% WG) and Bacillus thuringiensis var. kurstaki (Biobit 16% WP) treatments produced between 22 ± 6% and 32 ± 5% pest mortality. All treatments significantly reduced plant defoliation compared with untreated controls. Application of 1 × 109 OBs L−1 was 3–4-fold more effective than chemical or B. thuringiensis treatments. Larvae acquired lethal infection more rapidly when feeding on tomato than banana plants, but this difference disappeared following >60 min of feeding. CONCLUSION This information should prove useful in the registration of ChchSNPV-TF1 as a bioinsecticide in the Canary Islands and Europe. © 2014 Society of Chemical Industry

  • caracterizacion bioquimica de un nucleopoliedrovirus de Chrysodeixis chalcites autoctono de espana
    Boletín de sanidad vegetal. Plagas, 2000
    Co-Authors: Delia Muñoz, Primitivo Caballero, J Amate, J J Lipa, Tomas Cabello Garcia, Pablo Barranco Vega, Rosa Murillo
    Abstract:

    En las poblaciones naturales de larvas de Chrysodeixis chalcites (Esper) que atacan a los cultivos horticolas de los invernaderos de Almeria se desarrollo, en 1997, una epizootia en la que se identifico como agente causal un baculovirus del genero Nucleopolyhedrovirus (NPV). El ADN genomico del aislado viral, obtenido a partir de poliedros purificados de larvas muertas por virosis, fue analizado con las enzimas de restriccion BglII, EcoRI y PstI. Este analisis, confirmo que se trataba de un virus unico cuyo perfil de restriccion, con las enzimas utilizadas, no presentaba similitud con los perfiles de restriccion de otros NPVs, previamente aislados en esa zona sobre otras especies de lepidopteros como Spodoptera exigua (SeMNPV-SP2) y Spodoptera littoralis (SlMNPV-SP1), o del NPV de Autographa californica (AcNPV-wt) que es la especie tipo del genero Nucleopolyhedrovirus. El analisis de las proteinas estructurales del virus tambien permitio discriminar este aislado de otros del mismo genero. Se trata, por tanto, del primer aislado de un NPV de C. chalcites, en nuestras condiciones de medio, y siguiendo la nomenclatura propuesta por Murphy et al (1995) se ha denominado ChChNPV-SP1. Ensayos preliminares de su espectro de huespedes indican que este virus es bastante especifico ya que solo resulto infectivo para larvas de C. chalcites, Plusia gamma (L) y Trichoplusia ni (Hub). En cambio, no fue infectivo, por ingestion, para distintos estadios larvarios de Helicoverpa armigera (Hub), Spodoptera exigua (Hub), Spodoptera littoralis (Boisduval) y Spodoptera frugiperda (J.E. Smith).

Monique M. Van Oers - One of the best experts on this subject based on the ideXlab platform.

  • protein composition of the occlusion derived virus of Chrysodeixis chalcites nucleopolyhedrovirus
    Virus Research, 2011
    Co-Authors: J M Vlak, Ikbal Agah Ince, Sjef Boeren, Monique M. Van Oers
    Abstract:

    Chrysodeixis chalcites nucleopolyhedrovirus (ChchNPV) is a group II NPV and its genome has 151 predicted open reading frames. In this study, the protein composition of ChchNPV occlusion derived virus (ODV) was determined by LC–MS/MS. Fifty-three proteins were identified in ChchNPV ODV particles. One ODV-protein is encoded by a gene so far unique to ChchNPV (Chch105). The two DNA photolyases PHR1 and PHR2, which are characteristic for ChchNPV and thought to be involved in repairing UV damage in viral DNA, were not detected in the ODVs. Comparison of the ODV proteins identified in ChchNPV and in three other baculoviruses enabled the identification of ten conserved ODV proteins (ODV-E18, ODV-E56, ODV-EC27, ODV-EC43, P6.9, P33, P49, P74, GP41, and VP39). In addition, the baculovirus per os infectivity factors PIF1, PIF2 and PIF3 were all detected in ChchNPV and these should be considered as conserved ODV proteins as well as they are absolutely required for oral infection. With the LC–MS/MS method used 22 viral proteins were detected, which were not identified as ODV proteins in previous studies.

  • establishment of a cell line from Chrysodeixis chalcites permissive for Chrysodeixis chalcites and trichoplusia ni nucleopolyhedrovirus
    Journal of Invertebrate Pathology, 2010
    Co-Authors: Dwight E Lynn, J M Vlak, Delia Muñoz, Elizabeth C Roode, Jan W M Van Lent, Monique M. Van Oers
    Abstract:

    A new cell line was established from the embryos of the insect Chrysodeixis chalcites (Lepidoptera, Noctuidae, Plusiinae). The cell line contains several morphologically different cell types and was distinguished from three other lepidopteran cell lines propagated in the laboratory by DNA amplification fingerprinting. The cultured cells, which we officially named WU-CcE-1 cells, were permissive for infection by C. chalcites nucleopolyhedrovirus (ChchNPV) and large numbers of occlusion bodies were produced that retained their infectivity for C. chalcites larvae. The CcE-1 cells were also permissive for Trichoplusia ni single nucleopolyhedrovirus (TnSNPV). ChchNPV could be passaged in these cells for at least four passages indicating that budded virus production was supported. Autographa californica multiple nucleopolyhedrovirus (AcMNPV) and Helicoverpa armigera (Hear) NPV both induced apoptosis in these cells. The results obtained indicate that the CcE-1 cell line will be a useful tool in the study of both ChchNPV and TnSNPV.

  • active dna photolyase encoded by a baculovirus from the insect Chrysodeixis chalcites
    DNA Repair, 2008
    Co-Authors: Monique M. Van Oers, J M Vlak, Margit H Lampen, Monika I Bajek, Andre P M Eker
    Abstract:

    The genome of Chrysodeixis chalcites nucleopolyhedrovirus (ChchNPV) contains two open reading frames, Cc-phr1 and Cc-phr2, which encode putative class II CPD-DNA photolyases. CPD-photolyases repair UV-induced pyrimidine cyclobutane dimers using visible light as an energy source. Expression of Cc-phr2 provided photolyase deficient Escherichia coli cells with photoreactivating activity indicating that Cc-phr2 encodes an active photolyase. In contrast, Cc-phr1 did not rescue the photolyase deficiency. Cc-phr2 was overexpressed in E. coli and the resulting photolyase was purified till apparent homogeneity. Spectral measurements indicated the presence of FAD, but a second chromophore appeared to be absent. Recombinant Cc-phr2 photolyase was found to bind specifically F0 (8-hydroxy-7,8-didemethyl-5-deazariboflavin), which is an antenna chromophore present in various photolyases.. After reconstitution, FAD and F0 were present in approximately equimolar amounts. In reconstituted photolyase the F0 chromophore is functionally active as judged from the increase in the in vitro repair activity. This study demonstrates for the first time that a functional photolyase is encoded by an insect virus, which may have implications for the design of a new generation of baculoviruses with improved performance in insect pest control.

  • genome sequence of Chrysodeixis chalcites nucleopolyhedrovirus a baculovirus with two dna photolyase genes
    Journal of General Virology, 2005
    Co-Authors: Monique M. Van Oers, Elisabeth A. Herniou, Marleen H C Abmahenkens, Joost C W De Groot, Sander Peters, J M Vlak
    Abstract:

    The complete genome sequence of a single nucleocapsid nucleopolyhedrovirus recently isolated from Chrysodeixis chalcites (ChchNPV) was determined. The viral genome has a size of 149622 bp and an overall G+C content of 39?1 mol%. The sequence contains 151 predicted open reading frames (ORFs) with a minimal size of 50 codons. The similarity of these ORFs with those of other completely sequenced baculoviruses was calculated using a newly developed database, named GECCO. Phylogenetic analysis of the whole genome confirmed the evolutionary relationship of ChchNPV with group II NPVs, as did the absence of the NPV group I-specific gp64 gene. It is the first group II NPV to encode proliferating cell nuclear antigen. Most noteworthy is the presence of two ORFs encoding a class II cyclobutane pyrimidine dimer DNA photolyase. These two ORFs share only 45% amino acid identity and have different promoter motifs. Twenty-two additional unique baculovirus genes were identified, including a gene encoding a novel putative RING finger protein with a possible homologue in poxviruses.

  • Identification and characterization of a DNA photolyase-containing baculovirus from Chrysodeixis chalcites.
    Virology, 2004
    Co-Authors: Monique M. Van Oers, Elisabeth A. Herniou, Magda Usmany, Gerben J. Messelink, Just M. Vlak
    Abstract:

    A hitherto unknown single nucleocapsid nucleopolyhedrovirus (SNPV) with a unique property was isolated from larvae of the looper Chrysodeixis chalcites (Lepidoptera, Noctuidae, Plusiinae). Polyhedrin, lef-8, and pif-2 gene sequences were obtained by PCR with degenerate primers and used for phylogenetic analysis. ChchNPV belonged to class II NPVs and its polyhedrin sequence was most similar to that of class II NPVs of other members of the subfamily Plusiinae. Further genetic characterization involved the random cloning of HindIII fragments into a plasmid vector and analysis by end-in sequencing. A gene so far unique to baculoviruses was identified, which encodes a putative DNA repair enzyme: cyclobutane pyrimidine dimer (CPD) DNA photolyase (dpl). The transcriptional activity of this gene was demonstrated in both ChchNPV-infected C. chalcites larvae and infected Trichoplusia ni High Five cells by RT-PCR and 5' and 3' RACE analysis. The possible role of this gene in the biology of the virus is discussed.

Delia Muñoz - One of the best experts on this subject based on the ideXlab platform.

  • remarkably efficient production of a highly insecticidal Chrysodeixis chalcites nucleopolyhedrovirus chchnpv isolate in its homologous host
    Pest Management Science, 2018
    Co-Authors: Alexandra Bernal, Oihane Simón, Trevor Williams, Primitivo Caballero, Delia Muñoz
    Abstract:

    Background A Chrysodeixis chalcites nucleopolyhedrovirus from the Canary Islands (ChchNPV-TF1) has proved to be effective for control of Chrysodeixis chalcites on banana crops. Commercialization of this virus as a bioinsecticide requires an efficient production system. Results The sixth instar (L6 ) was the most suitable for virus production, producing 1.80 × 1011 occlusion bodies (OB)/larva and showed a lower prevalence of cannibalism (5.4%) than fourth (L4 ) or fifth (L5 ) instars. Inoculation of L6 at 24 h post molting produced six times more OB (5.72 × 1011 OB/larva) than recently molted L6 larvae (1.00 × 1011 OB/larva). No significant differences were recorded in mean time to death (165-175 h) or OB production per larva (3.75 × 1011 to 5.97 × 1011 ) or per mg larval weight (1.30 × 1011 to 2.11 × 109 ), in larvae inoculated with a range of inoculum concentrations (LC50 -LC90 ). Groups of infected L6 larvae reared at a density of 150 larvae/container produced a greater total number of OBs (8.07 × 1013 OB/container) than lower densities (25, 50 and 100 OB/container), and a similar number to containers with 200 inoculated larvae (8.43 × 1013 OB/container). Conclusion The processes described here allow efficient production of sufficient OBs to treat ∼ 40 ha of banana crops using the insects from a single container. © 2018 Society of Chemical Industry.

  • Efficacy of an alphabaculovirus-based biological insecticide for control of Chrysodeixis chalcites (Lepidoptera: Noctuidae) on tomato and banana crops.
    Pest management science, 2015
    Co-Authors: Oihane Simón, Trevor Williams, Alexandra Bernal, Aurelio Carnero, Estrella Hernández-suárez, Delia Muñoz, Primitivo Caballero
    Abstract:

    BACKGROUND Chrysodeixis chalcites (Esper) is a major pest of tomato in Mediterranean countries and attacks banana in the Canary Islands (Spain). The efficacy of Chrysodeixis chalcites single nucleopolyhedrovirus (ChchSNPV-TF1) was evaluated in plant growth chambers and greenhouse trials performed on tomato and banana plants respectively. Treatments were applied using a compressed air sprayer. RESULTS Mean (± SE) lethal infection varied from 77 ± 10% to 94 ± 3% in second-instar larvae fed for 2 days on tomato plants treated with 2 × 106 to 5 × 107 virus occlusion bodies (OBs) L−1, increasing to ∼100% infection after 7 days. Mortality of larvae collected from banana at different intervals post-application varied from 54 ± 10% to 96 ± 4% in treatments involving 1 × 108–1 × 109 OBs L−1, whereas indoxacarb (Steward 30% WG) and Bacillus thuringiensis var. kurstaki (Biobit 16% WP) treatments produced between 22 ± 6% and 32 ± 5% pest mortality. All treatments significantly reduced plant defoliation compared with untreated controls. Application of 1 × 109 OBs L−1 was 3–4-fold more effective than chemical or B. thuringiensis treatments. Larvae acquired lethal infection more rapidly when feeding on tomato than banana plants, but this difference disappeared following >60 min of feeding. CONCLUSION This information should prove useful in the registration of ChchSNPV-TF1 as a bioinsecticide in the Canary Islands and Europe. © 2014 Society of Chemical Industry

  • establishment of a cell line from Chrysodeixis chalcites permissive for Chrysodeixis chalcites and trichoplusia ni nucleopolyhedrovirus
    Journal of Invertebrate Pathology, 2010
    Co-Authors: Dwight E Lynn, J M Vlak, Delia Muñoz, Elizabeth C Roode, Jan W M Van Lent, Monique M. Van Oers
    Abstract:

    A new cell line was established from the embryos of the insect Chrysodeixis chalcites (Lepidoptera, Noctuidae, Plusiinae). The cell line contains several morphologically different cell types and was distinguished from three other lepidopteran cell lines propagated in the laboratory by DNA amplification fingerprinting. The cultured cells, which we officially named WU-CcE-1 cells, were permissive for infection by C. chalcites nucleopolyhedrovirus (ChchNPV) and large numbers of occlusion bodies were produced that retained their infectivity for C. chalcites larvae. The CcE-1 cells were also permissive for Trichoplusia ni single nucleopolyhedrovirus (TnSNPV). ChchNPV could be passaged in these cells for at least four passages indicating that budded virus production was supported. Autographa californica multiple nucleopolyhedrovirus (AcMNPV) and Helicoverpa armigera (Hear) NPV both induced apoptosis in these cells. The results obtained indicate that the CcE-1 cell line will be a useful tool in the study of both ChchNPV and TnSNPV.

  • caracterizacion bioquimica de un nucleopoliedrovirus de Chrysodeixis chalcites autoctono de espana
    Boletín de sanidad vegetal. Plagas, 2000
    Co-Authors: Delia Muñoz, Primitivo Caballero, J Amate, J J Lipa, Tomas Cabello Garcia, Pablo Barranco Vega, Rosa Murillo
    Abstract:

    En las poblaciones naturales de larvas de Chrysodeixis chalcites (Esper) que atacan a los cultivos horticolas de los invernaderos de Almeria se desarrollo, en 1997, una epizootia en la que se identifico como agente causal un baculovirus del genero Nucleopolyhedrovirus (NPV). El ADN genomico del aislado viral, obtenido a partir de poliedros purificados de larvas muertas por virosis, fue analizado con las enzimas de restriccion BglII, EcoRI y PstI. Este analisis, confirmo que se trataba de un virus unico cuyo perfil de restriccion, con las enzimas utilizadas, no presentaba similitud con los perfiles de restriccion de otros NPVs, previamente aislados en esa zona sobre otras especies de lepidopteros como Spodoptera exigua (SeMNPV-SP2) y Spodoptera littoralis (SlMNPV-SP1), o del NPV de Autographa californica (AcNPV-wt) que es la especie tipo del genero Nucleopolyhedrovirus. El analisis de las proteinas estructurales del virus tambien permitio discriminar este aislado de otros del mismo genero. Se trata, por tanto, del primer aislado de un NPV de C. chalcites, en nuestras condiciones de medio, y siguiendo la nomenclatura propuesta por Murphy et al (1995) se ha denominado ChChNPV-SP1. Ensayos preliminares de su espectro de huespedes indican que este virus es bastante especifico ya que solo resulto infectivo para larvas de C. chalcites, Plusia gamma (L) y Trichoplusia ni (Hub). En cambio, no fue infectivo, por ingestion, para distintos estadios larvarios de Helicoverpa armigera (Hub), Spodoptera exigua (Hub), Spodoptera littoralis (Boisduval) y Spodoptera frugiperda (J.E. Smith).

J M Vlak - One of the best experts on this subject based on the ideXlab platform.

  • protein composition of the occlusion derived virus of Chrysodeixis chalcites nucleopolyhedrovirus
    Virus Research, 2011
    Co-Authors: J M Vlak, Ikbal Agah Ince, Sjef Boeren, Monique M. Van Oers
    Abstract:

    Chrysodeixis chalcites nucleopolyhedrovirus (ChchNPV) is a group II NPV and its genome has 151 predicted open reading frames. In this study, the protein composition of ChchNPV occlusion derived virus (ODV) was determined by LC–MS/MS. Fifty-three proteins were identified in ChchNPV ODV particles. One ODV-protein is encoded by a gene so far unique to ChchNPV (Chch105). The two DNA photolyases PHR1 and PHR2, which are characteristic for ChchNPV and thought to be involved in repairing UV damage in viral DNA, were not detected in the ODVs. Comparison of the ODV proteins identified in ChchNPV and in three other baculoviruses enabled the identification of ten conserved ODV proteins (ODV-E18, ODV-E56, ODV-EC27, ODV-EC43, P6.9, P33, P49, P74, GP41, and VP39). In addition, the baculovirus per os infectivity factors PIF1, PIF2 and PIF3 were all detected in ChchNPV and these should be considered as conserved ODV proteins as well as they are absolutely required for oral infection. With the LC–MS/MS method used 22 viral proteins were detected, which were not identified as ODV proteins in previous studies.

  • baculovirus cyclobutane pyrimidine dimer photolyases show a close relationship with lepidopteran host homologues
    Insect Molecular Biology, 2011
    Co-Authors: M A Biernat, V I D Ros, J M Vlak, M M Van Oers
    Abstract:

    Cyclobutane pyrimidine dimer (CPD) photolyases repair ultraviolet (UV)-induced DNA damage using blue light. To get insight in the origin of baculovirus CPD photolyase (phr) genes, homologues in the lepidopteran insects Chrysodeixis chalcites, Spodoptera exigua and Trichoplusia ni were identified and characterized. Lepidopteran and baculovirus phr genes each form a monophyletic group, and together form a well-supported clade within the insect photolyases. This suggests that baculoviruses obtained their phr genes from an ancestral lepidopteran insect host. A likely evolutionary scenario is that a granulovirus, Spodoptera litura GV or a direct ancestor, obtained a phr gene. Subsequently, it was horizontally transferred from this granulovirus to several group II nucleopolyhedroviruses (NPVs), including those that infect noctuids of the Plusiinae subfamily.

  • establishment of a cell line from Chrysodeixis chalcites permissive for Chrysodeixis chalcites and trichoplusia ni nucleopolyhedrovirus
    Journal of Invertebrate Pathology, 2010
    Co-Authors: Dwight E Lynn, J M Vlak, Delia Muñoz, Elizabeth C Roode, Jan W M Van Lent, Monique M. Van Oers
    Abstract:

    A new cell line was established from the embryos of the insect Chrysodeixis chalcites (Lepidoptera, Noctuidae, Plusiinae). The cell line contains several morphologically different cell types and was distinguished from three other lepidopteran cell lines propagated in the laboratory by DNA amplification fingerprinting. The cultured cells, which we officially named WU-CcE-1 cells, were permissive for infection by C. chalcites nucleopolyhedrovirus (ChchNPV) and large numbers of occlusion bodies were produced that retained their infectivity for C. chalcites larvae. The CcE-1 cells were also permissive for Trichoplusia ni single nucleopolyhedrovirus (TnSNPV). ChchNPV could be passaged in these cells for at least four passages indicating that budded virus production was supported. Autographa californica multiple nucleopolyhedrovirus (AcMNPV) and Helicoverpa armigera (Hear) NPV both induced apoptosis in these cells. The results obtained indicate that the CcE-1 cell line will be a useful tool in the study of both ChchNPV and TnSNPV.

  • active dna photolyase encoded by a baculovirus from the insect Chrysodeixis chalcites
    DNA Repair, 2008
    Co-Authors: Monique M. Van Oers, J M Vlak, Margit H Lampen, Monika I Bajek, Andre P M Eker
    Abstract:

    The genome of Chrysodeixis chalcites nucleopolyhedrovirus (ChchNPV) contains two open reading frames, Cc-phr1 and Cc-phr2, which encode putative class II CPD-DNA photolyases. CPD-photolyases repair UV-induced pyrimidine cyclobutane dimers using visible light as an energy source. Expression of Cc-phr2 provided photolyase deficient Escherichia coli cells with photoreactivating activity indicating that Cc-phr2 encodes an active photolyase. In contrast, Cc-phr1 did not rescue the photolyase deficiency. Cc-phr2 was overexpressed in E. coli and the resulting photolyase was purified till apparent homogeneity. Spectral measurements indicated the presence of FAD, but a second chromophore appeared to be absent. Recombinant Cc-phr2 photolyase was found to bind specifically F0 (8-hydroxy-7,8-didemethyl-5-deazariboflavin), which is an antenna chromophore present in various photolyases.. After reconstitution, FAD and F0 were present in approximately equimolar amounts. In reconstituted photolyase the F0 chromophore is functionally active as judged from the increase in the in vitro repair activity. This study demonstrates for the first time that a functional photolyase is encoded by an insect virus, which may have implications for the design of a new generation of baculoviruses with improved performance in insect pest control.

  • genome sequence of Chrysodeixis chalcites nucleopolyhedrovirus a baculovirus with two dna photolyase genes
    Journal of General Virology, 2005
    Co-Authors: Monique M. Van Oers, Elisabeth A. Herniou, Marleen H C Abmahenkens, Joost C W De Groot, Sander Peters, J M Vlak
    Abstract:

    The complete genome sequence of a single nucleocapsid nucleopolyhedrovirus recently isolated from Chrysodeixis chalcites (ChchNPV) was determined. The viral genome has a size of 149622 bp and an overall G+C content of 39?1 mol%. The sequence contains 151 predicted open reading frames (ORFs) with a minimal size of 50 codons. The similarity of these ORFs with those of other completely sequenced baculoviruses was calculated using a newly developed database, named GECCO. Phylogenetic analysis of the whole genome confirmed the evolutionary relationship of ChchNPV with group II NPVs, as did the absence of the NPV group I-specific gp64 gene. It is the first group II NPV to encode proliferating cell nuclear antigen. Most noteworthy is the presence of two ORFs encoding a class II cyclobutane pyrimidine dimer DNA photolyase. These two ORFs share only 45% amino acid identity and have different promoter motifs. Twenty-two additional unique baculovirus genes were identified, including a gene encoding a novel putative RING finger protein with a possible homologue in poxviruses.

Oihane Simón - One of the best experts on this subject based on the ideXlab platform.

  • remarkably efficient production of a highly insecticidal Chrysodeixis chalcites nucleopolyhedrovirus chchnpv isolate in its homologous host
    Pest Management Science, 2018
    Co-Authors: Alexandra Bernal, Oihane Simón, Trevor Williams, Primitivo Caballero, Delia Muñoz
    Abstract:

    Background A Chrysodeixis chalcites nucleopolyhedrovirus from the Canary Islands (ChchNPV-TF1) has proved to be effective for control of Chrysodeixis chalcites on banana crops. Commercialization of this virus as a bioinsecticide requires an efficient production system. Results The sixth instar (L6 ) was the most suitable for virus production, producing 1.80 × 1011 occlusion bodies (OB)/larva and showed a lower prevalence of cannibalism (5.4%) than fourth (L4 ) or fifth (L5 ) instars. Inoculation of L6 at 24 h post molting produced six times more OB (5.72 × 1011 OB/larva) than recently molted L6 larvae (1.00 × 1011 OB/larva). No significant differences were recorded in mean time to death (165-175 h) or OB production per larva (3.75 × 1011 to 5.97 × 1011 ) or per mg larval weight (1.30 × 1011 to 2.11 × 109 ), in larvae inoculated with a range of inoculum concentrations (LC50 -LC90 ). Groups of infected L6 larvae reared at a density of 150 larvae/container produced a greater total number of OBs (8.07 × 1013 OB/container) than lower densities (25, 50 and 100 OB/container), and a similar number to containers with 200 inoculated larvae (8.43 × 1013 OB/container). Conclusion The processes described here allow efficient production of sufficient OBs to treat ∼ 40 ha of banana crops using the insects from a single container. © 2018 Society of Chemical Industry.

  • Chrysodeixis chalcites nucleopolyhedrovirus chchnpv natural occurrence and efficacy as a biological insecticide on young banana plants in greenhouse and open field conditions on the canary islands
    PLOS ONE, 2017
    Co-Authors: Ernesto Gabriel Fuentes, Oihane Simón, Trevor Williams, Primitivo Caballero, Estrella Hernandezsuarez
    Abstract:

    Chrysodeixis chalcites, an important pest of banana crops on the Canary Islands, is usually controlled by chemical insecticides. The present study aimed to evaluate the efficacy of the most prevalent isolate of the Chrysodeixis chalcites nucleopolyhedrovirus (ChchNPV, Baculoviridae) as a biological insecticide. Overall the prevalence of ChchNPV infection in C. chalcites populations was 2.3% (103 infected larvae out of 4,438 sampled), but varied from 0–4.8% on Tenerife and was usually low (0–2%) on the other islands. On Tenerife, infected larvae were present at 11 out of 17 plantations sampled. The prevalence of infection in larvae on bananas grown under greenhouse structures was significantly higher (3%) than in open-field sites (1.4%). The ChchNPV-TF1 isolate was the most abundant and widespread of four genetic variants of the virus. Application of 1.0x109 viral occlusion bodies (OBs)/l of ChchNPV-TF1 significantly reduced C. chalcites foliar damage in young banana plants as did commonly used pesticides, both in greenhouse and open-field sites. The insecticidal efficacy of ChchNPV-TF1 was similar to that of indoxacarb and a Bacillus thuringiensis (Bt)-based insecticide in one year of trials and similar to Bt in the following year of trails in greenhouse and field crops. However, larvae collected at different time intervals following virus treatments and reared in the laboratory experienced 2–7 fold more mortality than insects from conventional insecticide treatments. This suggests that the acquisition of lethal dose occurred over an extended period (up to 7 days) compared to a brief peak in larvae on plants treated with conventional insecticides. These results should prove useful for the registration of a ChchNPV-based insecticide for integrated management of this pest in banana crops on the Canary Islands.

  • Restriction endonuclease analysis of LaolNPV DNA.
    2017
    Co-Authors: Oihane Simón, Martin A. Erlandson, Marie Frayssinet, Trevor Williams, David A. Theilmann, Anne-nathalie Volkoff, Primitivo Caballero
    Abstract:

    Restriction endonuclease profiles following digestion of A) genomic DNAs of the seven isolates of LaolNPV collected in alfalfa crops nearby Montpellier with BglII, EcoRI and PstI enzymes, B) genomic DNAs of Chrysodeixis chalcites NPV (Chch), Helicoverpa armigera SNPV (Hear), Spodoptera littoralis (Spli), Spodopera exigua MNPV (Se) and the virus under study (LaolNPV) with BamHI, BglII, EcoRI and PstI, and C) genomic DNAs of Mamestra brassicae MNPV (Mb), Mamestra configurata NPV-A (MacoA), Mamestra configurata NPV-B (MacoB) and LaolNPV with BglII, EcoRI and PstI.

  • Efficacy of an alphabaculovirus-based biological insecticide for control of Chrysodeixis chalcites (Lepidoptera: Noctuidae) on tomato and banana crops.
    Pest management science, 2015
    Co-Authors: Oihane Simón, Trevor Williams, Alexandra Bernal, Aurelio Carnero, Estrella Hernández-suárez, Delia Muñoz, Primitivo Caballero
    Abstract:

    BACKGROUND Chrysodeixis chalcites (Esper) is a major pest of tomato in Mediterranean countries and attacks banana in the Canary Islands (Spain). The efficacy of Chrysodeixis chalcites single nucleopolyhedrovirus (ChchSNPV-TF1) was evaluated in plant growth chambers and greenhouse trials performed on tomato and banana plants respectively. Treatments were applied using a compressed air sprayer. RESULTS Mean (± SE) lethal infection varied from 77 ± 10% to 94 ± 3% in second-instar larvae fed for 2 days on tomato plants treated with 2 × 106 to 5 × 107 virus occlusion bodies (OBs) L−1, increasing to ∼100% infection after 7 days. Mortality of larvae collected from banana at different intervals post-application varied from 54 ± 10% to 96 ± 4% in treatments involving 1 × 108–1 × 109 OBs L−1, whereas indoxacarb (Steward 30% WG) and Bacillus thuringiensis var. kurstaki (Biobit 16% WP) treatments produced between 22 ± 6% and 32 ± 5% pest mortality. All treatments significantly reduced plant defoliation compared with untreated controls. Application of 1 × 109 OBs L−1 was 3–4-fold more effective than chemical or B. thuringiensis treatments. Larvae acquired lethal infection more rapidly when feeding on tomato than banana plants, but this difference disappeared following >60 min of feeding. CONCLUSION This information should prove useful in the registration of ChchSNPV-TF1 as a bioinsecticide in the Canary Islands and Europe. © 2014 Society of Chemical Industry