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A K Charnley - One of the best experts on this subject based on the ideXlab platform.
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the influence of temperature on the susceptibility of vine weevil Otiorhynchus sulcatus fabricius coleoptera curculionidae larvae to metarhizium anisopliae deuteromycotina hyphomycetes
Annals of Applied Biology, 1994Co-Authors: E R Moorhouse, A T Gillespie, A K CharnleyAbstract:Summary Mortality of Otiorhynchus sulcatus (Fabricius) larvae at 10oC, 15oC, 20oC and 25oC following treatment with 107conidia ml“1suspensions of six Metarhizium anisopliae (Metschnikoff) Sorokin isolates was temperature dependent. In all cases, the LT50s were inversely related to temperature, but the nature of this response varied between isolates. Strain 101-82 was the most virulent isolate at 25oC with an LT50 of 3.7 days, but it was the least virulent isolate at 15oC and it failed to kill any O. sulcatus larvae at 10oC. In contrast, strain 159-83 had the lowest virulence at both 20oC and 25oC, whereas it was the most virulent isolate at 10oC with an LT50 of 20.0 days. The mortality rates followed a similar pattern and were positively related to temperature in all cases with the exception of strain 159-83 at 25oC. Mycosis development was examined on larvae treated with strain 275-86 and significant differences were obtained between all four temperatures. Sporulation commenced after approximately 2.75 days at 25oC, but took nearly 11 days at 10oC. The infection rates also varied between temperatures; sporulation occurred on 98% of the treated larvae at 25oC, but only on 93%, 87% and 49% of the larvae at 20oC, 15oC and 10oC, respectively. The results of these bioassays demonstrate that temperature has a significant effect on the virulence of M. anisopliae. The differences between fungal strains also emphasises the importance of selecting isolates for specific situations on the basis of their temperature profiles.
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laboratory selection of metarhizium spp isolates for control of vine weevil larvae Otiorhynchus sulcatus
Journal of Invertebrate Pathology, 1993Co-Authors: E R Moorhouse, A T Gillespie, A K CharnleyAbstract:Abstract The susceptibility of Otiorhynchus sulcatus larvae to 19 isolates of the genus Metarhizium was examined at 20°C. All the Metarhizium anisopliae var. anisopliae isolates were pathogenic, with LT 50 S ranging from 6.09 to 8.72 days. The M. anisopliae var. majus strains were also pathogenic, but less virulent than the var. anisopliae strains, whereas nearly all the Metarhizium flavoviride and Metarhizium album strains had low virulence or were nonpathogenic. There were significant differences between the LT 50 s of the virulent var. anisopliae strains and there were also significant differences between the LT 50 s of the var. majus strains. There was no indication that the var. anisopliae isolates were specific to their original hosts because only one of the four most virulent strains was isolated from O. sulcatus . Two of the other highly virulent strains originated from Coleopteran hosts and the fourth strain was isolated from a Lepidopteran larva. Mycosis development was correlated with strain virulence and there were significant differences between strains. Mycelial emergence was observed 1.5 days after the death of larvae treated with a highly virulent var. anisopliae strain, whereas it occurred after 3 days with a less virulent var. majus strain. Sporulation occurred 2 to 3 days after mycelial emergence on larvae infected by most strains with the exception of one var. anisopliae and one var. majus strain. Sporulation on larvae treated with these two strains was variable and extensive mycelial development was often observed. The results of the bioassay assessments suggest that the most virulent strains may have potential as biological control agents for O. sulcatus and this now needs to be evaluated in pot and field trials using a range of plant species under different growing systems.
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selection of virulent and persistent metarhizium anisopliae isolates to control black vine weevil Otiorhynchus sulcatus larvae on glasshouse begonia
Journal of Invertebrate Pathology, 1993Co-Authors: E R Moorhouse, A T Gillespie, A K CharnleyAbstract:Abstract The virulence of 10 Metarhizium anisopliae isolates against black vine weevil, Otiorhynchus sulcatus, larvae was examined in the glasshouse using potted Begonia. The most virulent isolate, 275-86, reduced larval numbers by 86% compared to the control population (pots treated with 0.05% Triton X-100 only) and two other M. anisopliae isolates reduced the larval population by over 80%. Only one isolate, 313-87, failed significantly to reduce the larval population. There were no significant differences between the six most virulent strains, however, four of these were significantly more virulent than 313-87. There was no significant correlation between larval number and plant biomass. Three M. anisopliae isolates were further examined for persistence in peat compost. All three strains significantly reduced larval numbers on Begonia compared with the control population. The highest levels of control were recorded with strain 100-82 (67-80%) which was significantly more virulent than strain 35-79. The fungal drenches were most effective when they were applied 8 weeks before the application of O. sulcatus eggs, however, significant levels of control were also recorded with spores which were applied 16 weeks before the eggs. Control with conidia applied 4 weeks after the eggs was significantly lower than that with the application 8 weeks before the eggs, suggesting that there might be differences in the levels of control achieved using curative and prophylactic spore applications. The results of these experiments demonstrate that M. anisopliae has considerable potential as a prophylactic microbial control agent for O. sulcatus in the glasshouse.
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application of metarhizium anisopliae metsch sor conidia to control Otiorhynchus sulcatus f coleoptera curculionidae larvae on glasshouse pot plants
Annals of Applied Biology, 1993Co-Authors: E R Moorhouse, A T Gillespie, A K CharnleyAbstract:Summary The efficacy of the entomogenous fungus Metarhizium anisopliae was assessed against vine weevil (Otiorhynchus sulcatus) larvae in the glasshouse. Prophylactic application of M. anisopliae conidia to begonia resulted in total larval control, but curative applications were less effective with only 65% control when conidial application was delayed until 8 weeks after egg infestation. Prophylactic applications also provided effective larval control on begonia plants which received multiple egg applications over a six week period. Larval mortality was monitored on cyclamen plants which had received a prophylactic drench of M. anisopliae conidia. The population was reduced by 78% within 5 weeks of egg application and control rose to 90% after 17 weeks, although the increase was not significant. Prophylactic conidial drenches were compared with a similar number of compost incorporated conidia on cyclamen, but there was no significant difference between the two spore application strategies. Application of M. anisopliae conidia to impatiens modules before potting-on resulted in over 89% larval control compared to over 97% control when a similar number of conidia were applied to the plants after potting. Larval control was further reduced to 79% when the module drenches were reduced to one quarter of the highest dose (5 × 107 compared to 2 × 108 conidia per module). The persistence of three M. anisopliae strains was examined over a 20 week period on impatiens. There was no overall decline in efficacy over this period, although there was variability in the performance of the different strains and it was suggested that this was linked to temperature. The results of these experiments suggest that M. anisopliae has considerable potential as a microbial control agent for O. sulcatus on glasshouse ornamentals.
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control of Otiorhynchus sulcatus fabricius coleoptera curculionidae larvae on a range of hardy ornamental nursery stock species using the entomogenous fungus metarhizium anisopliae
Biocontrol Science and Technology, 1993Co-Authors: E R Moorhouse, M A Easterbrook, A T Gillespie, A K CharnleyAbstract:The potential of the entomogenous fungus Metarhizium anisopliae as a microbial control agent for vine weevil (Otiorhynchus sulcatus) larvae was examined on a range of outdoor hardy nursery stock species. A curative application of M. anisopliae conidia (5× 108 conidia l‐1compost) reduced larval numbers by 62% on Skimmia japonica ’Rubella’ and by up to 43% on Viburnum plicatum ’Mariesii’. Four M. anisopliae isolates were examined and all reduced the larval populations on both species. However, the reductions were only significant with strains 159–83 and 100–82 on S. japonica ’Rubella’ and 100–82 on V. plicatum ’Mariesii’. Larval development on two other species (Hydrangea macrophylla ’Blue Wave’ and Thuja plicata ’Zebrina') which had been treated with 0.05% Triton X‐100 (the control treatment) was very poor and therefore it was not possible to determine whether or not the fungal drench had any effect. The experiment was repeated in the following year at two different sites, East Mailing and Littlehampton, u...
E R Moorhouse - One of the best experts on this subject based on the ideXlab platform.
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the influence of temperature on the susceptibility of vine weevil Otiorhynchus sulcatus fabricius coleoptera curculionidae larvae to metarhizium anisopliae deuteromycotina hyphomycetes
Annals of Applied Biology, 1994Co-Authors: E R Moorhouse, A T Gillespie, A K CharnleyAbstract:Summary Mortality of Otiorhynchus sulcatus (Fabricius) larvae at 10oC, 15oC, 20oC and 25oC following treatment with 107conidia ml“1suspensions of six Metarhizium anisopliae (Metschnikoff) Sorokin isolates was temperature dependent. In all cases, the LT50s were inversely related to temperature, but the nature of this response varied between isolates. Strain 101-82 was the most virulent isolate at 25oC with an LT50 of 3.7 days, but it was the least virulent isolate at 15oC and it failed to kill any O. sulcatus larvae at 10oC. In contrast, strain 159-83 had the lowest virulence at both 20oC and 25oC, whereas it was the most virulent isolate at 10oC with an LT50 of 20.0 days. The mortality rates followed a similar pattern and were positively related to temperature in all cases with the exception of strain 159-83 at 25oC. Mycosis development was examined on larvae treated with strain 275-86 and significant differences were obtained between all four temperatures. Sporulation commenced after approximately 2.75 days at 25oC, but took nearly 11 days at 10oC. The infection rates also varied between temperatures; sporulation occurred on 98% of the treated larvae at 25oC, but only on 93%, 87% and 49% of the larvae at 20oC, 15oC and 10oC, respectively. The results of these bioassays demonstrate that temperature has a significant effect on the virulence of M. anisopliae. The differences between fungal strains also emphasises the importance of selecting isolates for specific situations on the basis of their temperature profiles.
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laboratory selection of metarhizium spp isolates for control of vine weevil larvae Otiorhynchus sulcatus
Journal of Invertebrate Pathology, 1993Co-Authors: E R Moorhouse, A T Gillespie, A K CharnleyAbstract:Abstract The susceptibility of Otiorhynchus sulcatus larvae to 19 isolates of the genus Metarhizium was examined at 20°C. All the Metarhizium anisopliae var. anisopliae isolates were pathogenic, with LT 50 S ranging from 6.09 to 8.72 days. The M. anisopliae var. majus strains were also pathogenic, but less virulent than the var. anisopliae strains, whereas nearly all the Metarhizium flavoviride and Metarhizium album strains had low virulence or were nonpathogenic. There were significant differences between the LT 50 s of the virulent var. anisopliae strains and there were also significant differences between the LT 50 s of the var. majus strains. There was no indication that the var. anisopliae isolates were specific to their original hosts because only one of the four most virulent strains was isolated from O. sulcatus . Two of the other highly virulent strains originated from Coleopteran hosts and the fourth strain was isolated from a Lepidopteran larva. Mycosis development was correlated with strain virulence and there were significant differences between strains. Mycelial emergence was observed 1.5 days after the death of larvae treated with a highly virulent var. anisopliae strain, whereas it occurred after 3 days with a less virulent var. majus strain. Sporulation occurred 2 to 3 days after mycelial emergence on larvae infected by most strains with the exception of one var. anisopliae and one var. majus strain. Sporulation on larvae treated with these two strains was variable and extensive mycelial development was often observed. The results of the bioassay assessments suggest that the most virulent strains may have potential as biological control agents for O. sulcatus and this now needs to be evaluated in pot and field trials using a range of plant species under different growing systems.
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selection of virulent and persistent metarhizium anisopliae isolates to control black vine weevil Otiorhynchus sulcatus larvae on glasshouse begonia
Journal of Invertebrate Pathology, 1993Co-Authors: E R Moorhouse, A T Gillespie, A K CharnleyAbstract:Abstract The virulence of 10 Metarhizium anisopliae isolates against black vine weevil, Otiorhynchus sulcatus, larvae was examined in the glasshouse using potted Begonia. The most virulent isolate, 275-86, reduced larval numbers by 86% compared to the control population (pots treated with 0.05% Triton X-100 only) and two other M. anisopliae isolates reduced the larval population by over 80%. Only one isolate, 313-87, failed significantly to reduce the larval population. There were no significant differences between the six most virulent strains, however, four of these were significantly more virulent than 313-87. There was no significant correlation between larval number and plant biomass. Three M. anisopliae isolates were further examined for persistence in peat compost. All three strains significantly reduced larval numbers on Begonia compared with the control population. The highest levels of control were recorded with strain 100-82 (67-80%) which was significantly more virulent than strain 35-79. The fungal drenches were most effective when they were applied 8 weeks before the application of O. sulcatus eggs, however, significant levels of control were also recorded with spores which were applied 16 weeks before the eggs. Control with conidia applied 4 weeks after the eggs was significantly lower than that with the application 8 weeks before the eggs, suggesting that there might be differences in the levels of control achieved using curative and prophylactic spore applications. The results of these experiments demonstrate that M. anisopliae has considerable potential as a prophylactic microbial control agent for O. sulcatus in the glasshouse.
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application of metarhizium anisopliae metsch sor conidia to control Otiorhynchus sulcatus f coleoptera curculionidae larvae on glasshouse pot plants
Annals of Applied Biology, 1993Co-Authors: E R Moorhouse, A T Gillespie, A K CharnleyAbstract:Summary The efficacy of the entomogenous fungus Metarhizium anisopliae was assessed against vine weevil (Otiorhynchus sulcatus) larvae in the glasshouse. Prophylactic application of M. anisopliae conidia to begonia resulted in total larval control, but curative applications were less effective with only 65% control when conidial application was delayed until 8 weeks after egg infestation. Prophylactic applications also provided effective larval control on begonia plants which received multiple egg applications over a six week period. Larval mortality was monitored on cyclamen plants which had received a prophylactic drench of M. anisopliae conidia. The population was reduced by 78% within 5 weeks of egg application and control rose to 90% after 17 weeks, although the increase was not significant. Prophylactic conidial drenches were compared with a similar number of compost incorporated conidia on cyclamen, but there was no significant difference between the two spore application strategies. Application of M. anisopliae conidia to impatiens modules before potting-on resulted in over 89% larval control compared to over 97% control when a similar number of conidia were applied to the plants after potting. Larval control was further reduced to 79% when the module drenches were reduced to one quarter of the highest dose (5 × 107 compared to 2 × 108 conidia per module). The persistence of three M. anisopliae strains was examined over a 20 week period on impatiens. There was no overall decline in efficacy over this period, although there was variability in the performance of the different strains and it was suggested that this was linked to temperature. The results of these experiments suggest that M. anisopliae has considerable potential as a microbial control agent for O. sulcatus on glasshouse ornamentals.
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control of Otiorhynchus sulcatus fabricius coleoptera curculionidae larvae on a range of hardy ornamental nursery stock species using the entomogenous fungus metarhizium anisopliae
Biocontrol Science and Technology, 1993Co-Authors: E R Moorhouse, M A Easterbrook, A T Gillespie, A K CharnleyAbstract:The potential of the entomogenous fungus Metarhizium anisopliae as a microbial control agent for vine weevil (Otiorhynchus sulcatus) larvae was examined on a range of outdoor hardy nursery stock species. A curative application of M. anisopliae conidia (5× 108 conidia l‐1compost) reduced larval numbers by 62% on Skimmia japonica ’Rubella’ and by up to 43% on Viburnum plicatum ’Mariesii’. Four M. anisopliae isolates were examined and all reduced the larval populations on both species. However, the reductions were only significant with strains 159–83 and 100–82 on S. japonica ’Rubella’ and 100–82 on V. plicatum ’Mariesii’. Larval development on two other species (Hydrangea macrophylla ’Blue Wave’ and Thuja plicata ’Zebrina') which had been treated with 0.05% Triton X‐100 (the control treatment) was very poor and therefore it was not possible to determine whether or not the fungal drench had any effect. The experiment was repeated in the following year at two different sites, East Mailing and Littlehampton, u...
A T Gillespie - One of the best experts on this subject based on the ideXlab platform.
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the influence of temperature on the susceptibility of vine weevil Otiorhynchus sulcatus fabricius coleoptera curculionidae larvae to metarhizium anisopliae deuteromycotina hyphomycetes
Annals of Applied Biology, 1994Co-Authors: E R Moorhouse, A T Gillespie, A K CharnleyAbstract:Summary Mortality of Otiorhynchus sulcatus (Fabricius) larvae at 10oC, 15oC, 20oC and 25oC following treatment with 107conidia ml“1suspensions of six Metarhizium anisopliae (Metschnikoff) Sorokin isolates was temperature dependent. In all cases, the LT50s were inversely related to temperature, but the nature of this response varied between isolates. Strain 101-82 was the most virulent isolate at 25oC with an LT50 of 3.7 days, but it was the least virulent isolate at 15oC and it failed to kill any O. sulcatus larvae at 10oC. In contrast, strain 159-83 had the lowest virulence at both 20oC and 25oC, whereas it was the most virulent isolate at 10oC with an LT50 of 20.0 days. The mortality rates followed a similar pattern and were positively related to temperature in all cases with the exception of strain 159-83 at 25oC. Mycosis development was examined on larvae treated with strain 275-86 and significant differences were obtained between all four temperatures. Sporulation commenced after approximately 2.75 days at 25oC, but took nearly 11 days at 10oC. The infection rates also varied between temperatures; sporulation occurred on 98% of the treated larvae at 25oC, but only on 93%, 87% and 49% of the larvae at 20oC, 15oC and 10oC, respectively. The results of these bioassays demonstrate that temperature has a significant effect on the virulence of M. anisopliae. The differences between fungal strains also emphasises the importance of selecting isolates for specific situations on the basis of their temperature profiles.
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laboratory selection of metarhizium spp isolates for control of vine weevil larvae Otiorhynchus sulcatus
Journal of Invertebrate Pathology, 1993Co-Authors: E R Moorhouse, A T Gillespie, A K CharnleyAbstract:Abstract The susceptibility of Otiorhynchus sulcatus larvae to 19 isolates of the genus Metarhizium was examined at 20°C. All the Metarhizium anisopliae var. anisopliae isolates were pathogenic, with LT 50 S ranging from 6.09 to 8.72 days. The M. anisopliae var. majus strains were also pathogenic, but less virulent than the var. anisopliae strains, whereas nearly all the Metarhizium flavoviride and Metarhizium album strains had low virulence or were nonpathogenic. There were significant differences between the LT 50 s of the virulent var. anisopliae strains and there were also significant differences between the LT 50 s of the var. majus strains. There was no indication that the var. anisopliae isolates were specific to their original hosts because only one of the four most virulent strains was isolated from O. sulcatus . Two of the other highly virulent strains originated from Coleopteran hosts and the fourth strain was isolated from a Lepidopteran larva. Mycosis development was correlated with strain virulence and there were significant differences between strains. Mycelial emergence was observed 1.5 days after the death of larvae treated with a highly virulent var. anisopliae strain, whereas it occurred after 3 days with a less virulent var. majus strain. Sporulation occurred 2 to 3 days after mycelial emergence on larvae infected by most strains with the exception of one var. anisopliae and one var. majus strain. Sporulation on larvae treated with these two strains was variable and extensive mycelial development was often observed. The results of the bioassay assessments suggest that the most virulent strains may have potential as biological control agents for O. sulcatus and this now needs to be evaluated in pot and field trials using a range of plant species under different growing systems.
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selection of virulent and persistent metarhizium anisopliae isolates to control black vine weevil Otiorhynchus sulcatus larvae on glasshouse begonia
Journal of Invertebrate Pathology, 1993Co-Authors: E R Moorhouse, A T Gillespie, A K CharnleyAbstract:Abstract The virulence of 10 Metarhizium anisopliae isolates against black vine weevil, Otiorhynchus sulcatus, larvae was examined in the glasshouse using potted Begonia. The most virulent isolate, 275-86, reduced larval numbers by 86% compared to the control population (pots treated with 0.05% Triton X-100 only) and two other M. anisopliae isolates reduced the larval population by over 80%. Only one isolate, 313-87, failed significantly to reduce the larval population. There were no significant differences between the six most virulent strains, however, four of these were significantly more virulent than 313-87. There was no significant correlation between larval number and plant biomass. Three M. anisopliae isolates were further examined for persistence in peat compost. All three strains significantly reduced larval numbers on Begonia compared with the control population. The highest levels of control were recorded with strain 100-82 (67-80%) which was significantly more virulent than strain 35-79. The fungal drenches were most effective when they were applied 8 weeks before the application of O. sulcatus eggs, however, significant levels of control were also recorded with spores which were applied 16 weeks before the eggs. Control with conidia applied 4 weeks after the eggs was significantly lower than that with the application 8 weeks before the eggs, suggesting that there might be differences in the levels of control achieved using curative and prophylactic spore applications. The results of these experiments demonstrate that M. anisopliae has considerable potential as a prophylactic microbial control agent for O. sulcatus in the glasshouse.
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application of metarhizium anisopliae metsch sor conidia to control Otiorhynchus sulcatus f coleoptera curculionidae larvae on glasshouse pot plants
Annals of Applied Biology, 1993Co-Authors: E R Moorhouse, A T Gillespie, A K CharnleyAbstract:Summary The efficacy of the entomogenous fungus Metarhizium anisopliae was assessed against vine weevil (Otiorhynchus sulcatus) larvae in the glasshouse. Prophylactic application of M. anisopliae conidia to begonia resulted in total larval control, but curative applications were less effective with only 65% control when conidial application was delayed until 8 weeks after egg infestation. Prophylactic applications also provided effective larval control on begonia plants which received multiple egg applications over a six week period. Larval mortality was monitored on cyclamen plants which had received a prophylactic drench of M. anisopliae conidia. The population was reduced by 78% within 5 weeks of egg application and control rose to 90% after 17 weeks, although the increase was not significant. Prophylactic conidial drenches were compared with a similar number of compost incorporated conidia on cyclamen, but there was no significant difference between the two spore application strategies. Application of M. anisopliae conidia to impatiens modules before potting-on resulted in over 89% larval control compared to over 97% control when a similar number of conidia were applied to the plants after potting. Larval control was further reduced to 79% when the module drenches were reduced to one quarter of the highest dose (5 × 107 compared to 2 × 108 conidia per module). The persistence of three M. anisopliae strains was examined over a 20 week period on impatiens. There was no overall decline in efficacy over this period, although there was variability in the performance of the different strains and it was suggested that this was linked to temperature. The results of these experiments suggest that M. anisopliae has considerable potential as a microbial control agent for O. sulcatus on glasshouse ornamentals.
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control of Otiorhynchus sulcatus fabricius coleoptera curculionidae larvae on a range of hardy ornamental nursery stock species using the entomogenous fungus metarhizium anisopliae
Biocontrol Science and Technology, 1993Co-Authors: E R Moorhouse, M A Easterbrook, A T Gillespie, A K CharnleyAbstract:The potential of the entomogenous fungus Metarhizium anisopliae as a microbial control agent for vine weevil (Otiorhynchus sulcatus) larvae was examined on a range of outdoor hardy nursery stock species. A curative application of M. anisopliae conidia (5× 108 conidia l‐1compost) reduced larval numbers by 62% on Skimmia japonica ’Rubella’ and by up to 43% on Viburnum plicatum ’Mariesii’. Four M. anisopliae isolates were examined and all reduced the larval populations on both species. However, the reductions were only significant with strains 159–83 and 100–82 on S. japonica ’Rubella’ and 100–82 on V. plicatum ’Mariesii’. Larval development on two other species (Hydrangea macrophylla ’Blue Wave’ and Thuja plicata ’Zebrina') which had been treated with 0.05% Triton X‐100 (the control treatment) was very poor and therefore it was not possible to determine whether or not the fungal drench had any effect. The experiment was repeated in the following year at two different sites, East Mailing and Littlehampton, u...
N. G. M. Hague - One of the best experts on this subject based on the ideXlab platform.
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influence of temperature on the production and infectivity of entomopathogenic nematodes against larvae and pupae of vine weevil Otiorhynchus sulcatus coleoptera curculionidae
Journal of Entomology, 2005Co-Authors: A N Mahar, N. G. M. Hague, D A Darban, A G Lanjar, M Munir, N D Jan, S R GowenAbstract:Susceptibility of late instar vine weevil Otiorhynchus sulcatus larvae and pupae to four species entomopathogenic nematodes were tested. Bioassays on production and infectivity to larvae and pupae were compared for two steinernematids and two heterorhabditis such as Steinernema carpocapsae, S. feltiae, Heterorhabditis indica and H. bacteriophora. Nematodes production of all species was determined by the number infective juveniles (IJs) established in vine weevil larvae and pupae O. sulcatus using sand and filter paper bioassay. S. feltiae produced the maximum number in larvae and pupae at 20°C as compared to other nematodes but production of H. indica, was better at 25°C in larvae and pupae followed by H. bacteriophora, S. carpocapsae and Infectivity test of larvae and pupae was also done in sand media. Infective juveniles recovered from larvae and pupae when infected with S. feltiae produced maximum infective juveniles at 20°C temperatures than all other isolates. H. bacteriophora produced higher number of IJs in larvae and pupae than all other nematode isolates at 25°C. This paper indicates the application of nematodes with the knowledge of insect pest biology represents a possible new strategy for O. sulcatus larvae and pupae.
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infection development and reproduction of the entomopathogenic nematode steinernema arenarium nematoda steinernematidae in the black vine weevil Otiorhynchus sulcatus coleoptera curculionidae
Nematology, 1999Co-Authors: Thomae Kakouliduarte, N. G. M. HagueAbstract:Steinernema arenarium (Nematoda: Steinernematidae) completed a single generation in larvae of Otiorhynchus sulcatus (F.) (Coleoptera: Curculionidae), at 23 degrees C. From the time of initial exposure of the insects to the nematodes, infection, formation of adults, and appearance of infective juveniles (IJ) occurred at 18, 48, and 120 h, respectively. In second instar (L2) O. sulcatus, small stunted females developed, but in late instar larvae (L6), stunted females co-existed with normal sized females. The stunted female nematodes developing in L6 O. sulcatus produced stunted progeny and the giant females normal sized IJ. The total body length and greatest body diameter of the larger IJ from O. sulcatus were similar to those recorded for normal sized IJ exiting Galleria mellonella (Lepidoptera: Pyralidae). The length of the small IJ was just over half the length of the large IJ produced in O. sulcatus and G. mellonella. IJ of both size groups were pathogenic to G. mellonella, and the small IJ matured into normal giant females within larger hosts. Small IJ of S. arenarium were able to infect L2 O. sulcatus in significantly higher numbers than normal sized IJ. The reasons for the single generation and production of stunted females and IJ are addressed. Infestation, developpement et reproduction du nematode entomopathogene Steinernema arenarium (Nematoda: Steinernematidae) sur Otiorhynchus sulcatus (Coleoptera: Curculionidae)- Steinernema arenarium (Nematoda: Steinernematidae) n'accomplit, a 23 degrees C, qu'une seule generation dans les larves d'Otiorhynchus sulcatus (F.) (Coleoptera: Curculionidae). A partir de la mise en presence de l'insecte et des nematodes, l'infestation, la formation des adultes et l'apparition des juveniles infestants (IJ) se produisent en, respectivement, 18, 48 et 120 heures. Dans les larves de deuxieme stade (L2) d'O. sulcatus il se developpe des femelles petites et rabougries tandis que dans les larves de dernier stade (L6) de petites femelles coexistent avec des femelles de taille normale. Les petites femelles du nematode qui se sont developpees dans les L6 d'O. sulcatus ont une descendance rabougrie tandis que les femelles geantes produisent des IJ de taille normale. La longueur du corps et le diametre maximal des plus grandes IJ provenant d'O. sulcatus sont equivalents a ceux des IJ de taille normale provenant de Galleria mellonella (Lepidoptera: Pyralidae). La longueur des petites IJ depasse de peu la moitie de celle des grandes IJ produites chez O. sulcatus et G. mellonella. Les IJ des deux groupes de taille sont pathogenes envers G. mellonella, et les petites IJ se developpent en femelles geantes, normales, dans des hotes de plus grande taille. Les petites IJ de S. arenarium peuvent infester O. sulcatus en nombre significativement plus eleve que les IJ de taille normale. Les causes de la generation unique et de la production de femelles et IJ rabougris sont discutees.
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Biological control of the black vine weevil, Otiorhynchus sulcatus (Coleoptera: Curculionidae) with entomopathogenic nematodes (Nematoda: Rhabditida)
Annals of Applied Biology, 1997Co-Authors: Thomais Kakouli-duarte, L. Labuschagne, N. G. M. HagueAbstract:Summary Trials conducted under glasshouse conditions showed that control of Otiorhynchus sulcatus larvae in strawberry plants can be effective using Steinernema carpocapsae and Heterorhabditis megidis, given that temperature and moisture extremes are avoided. In field experiments, the double line T-Tape® drip irrigation system performed better than the single line T-Tape® system, effectively distributing the nematodes along and across strawberry raised beds, and placing them close to the root zone where O. sulcatus larvae feed. As soil temperatures are satisfactory for nematode infectivity from late spring to early autumn, nematode applications were aimed at late instar larvae during spring, and early instar larvae during summer. Late summer field treatment with S. carpocapsae induced 49.5% reduction of the early instar larvae, and field application of the same nematode species in late spring resulted in 65% control of late instar larvae. In the same trial, spring application of H. megidis caused 26% mortality of late instar larvae of O. sulcatus.
Denny J Bruck - One of the best experts on this subject based on the ideXlab platform.
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field attraction of the vine weevil Otiorhynchus sulcatus to kairomones
Journal of Economic Entomology, 2012Co-Authors: Denny J Bruck, F C Griepink, Willem Jan De KogelAbstract:ABSTRACT Root weevils in the genus Otiorhynchus are cited as one of the most important pests in the major nursery and small fruit production areas throughout the United States, western Canada, and northern Europe. A major problem in combating weevil attack is monitoring and timing of control measures. Because of the night-activity of the adult weevils growers do not observe the emerging weevils in a timely manner and oviposition often starts before effective control measures are taken. Several vine weevil electroantennogram-active plant volatiles were identified from a preferred host plant, Euonymus fortunei. Main compounds evoking antennal responses on the weevils' antennae were (Z)-2-pentenol, (E)-2-hexenol, (Z)-3-hexenol, methyl benzoate, linalool, (E)-4,8-dimethyl-1,3,7-nonatriene, methyl eugenol, and (E, E)-α-farnesene. Several of these compounds were tested alone and in mixtures on attractiveness for the vine weevil Otiorhynchus sulcatus (F.) in field-grown strawberry in Oregon. O. sulcatus were att...
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effects of a novel microsporidium on the black vine weevil Otiorhynchus sulcatus f coleoptera curculionidae
Journal of Invertebrate Pathology, 2008Co-Authors: Denny J Bruck, Leellen F Solter, Amanda LakeAbstract:A newly discovered microsporidium infecting the black vine weevil, Otiorhynchus sulcatus (F.) (Coleoptera: Curculionidae), provisionally placed in the genus Canningia, was studied to determine its impact on O. sulcatus. O. sulcatus populations from several locations were sampled and evaluated for microsporidiosis. A very low prevalence of the disease was observed in all locations surveyed (<3.0%). Laboratory studies were conducted by orally exposing both larvae and adults of O. sulcatus to varying concentrations of Canningia sp. spores. Larval bioassays at a variety of dosages (0, 10, etc.) were performed to evaluate pathogen infectivity, larval survival and growth. Adult bioassays (dosages: 0, 10, etc.) were performed to evaluate longevity, fecundity and mechanisms of vertical pathogen transmission. Larvae and adults were infected in all spore treatments. Larval growth was significantly reduced at dosages above 10 spores/larva. Adults infected at all dosages experienced high levels of mortality and fecundity was reduced to zero. Greenhouse trials were performed to determine if larvae feeding in soil acquired infections when spores were topically applied as a drench application (0, 10(5), 10(6), 10(7) spores/pot). Established larvae feeding on plant roots in pots developed infections when exposed to drench treatments of 10(6) and 10(7) spores/pot after 14-21 days. Canningia sp. is an acute pathogen of O. sulcatus infective to both larvae and adults. Topically applied spores also infected larvae feeding on roots in soilless potting media, suggesting the possibility of using this pathogen in a microbial control program.
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efficacy of metarhizium anisopliae as a curative application for black vine weevil Otiorhynchus sulcatus infesting container grown nursery crops
Journal of environmental horticulture, 2007Co-Authors: Denny J BruckAbstract:Abstract The black vine weevil (BVW), Otiorhynchus sulcatus (F.) is a serious pest of nursery crops. The fungus, Metarhizium anisopliae (F52), is registered by the U.S. Environmental Protection Agency for BVW control. The objectives of this study were to determine the efficacy of a curative drench application of M. anisopliae for controlling BVW larval infestations in container-grown nursery plants and the effect of temperature on the rate of fungal growth and speed of kill. Trials evaluating the efficacy of M. anisopliae as a curative application were performed in the spring of 2004 and 2005 as well as the fall of 2006. Laboratory studies were performed to quantify the impact of temperature (10, 15, 20, 24 and 28C) on fungal growth and speed of kill. Metarhizium anisopliae applied in the greenhouse and outdoors in 2004 were 92 and 30% effective, respectively. Fungal applications to container-grown plant material maintained outdoors in the spring of 2005 were nearly 100% effective 28 days after applicatio...
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natural occurrence of entomopathogens in pacific northwest nursery soils and their virulence to the black vine weevil Otiorhynchus sulcatus f coleoptera curculionidae
Environmental Entomology, 2004Co-Authors: Denny J BruckAbstract:Abstract The black vine weevil Otiorhynchus sulcatus (F.) is the primary insect pest of field and container-grown woody ornamentals in the Pacific Northwest (PNW). These studies were conducted to determine the natural occurrence of soil-borne entomopathogens in PNW nursery soils and determine their virulence to black vine weevil. Soil samples were collected July–September of 2002 from field-grown woody ornamental nursery stock in Oregon, Washington, and Idaho. Sample collection in each state took place in the major nursery production areas. A total of 280 samples was collected (Oregon, 170; Washington, 50; Idaho, 60). Entomopathogens were isolated using insect baiting (nematodes and fungi) as well as semiselective media (fungi). Bacillus thuringiensis Berliner was isolated through sodium acetate selection. Soil-borne entomopathogenic fungi occur widely throughout the major nursery production areas in the PNW. The entomopathogenic fungi Metarhizium anisopliae (Metchnikoff) Sorokin, Beauveria bassiana (Bals...
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a technique for continuous mass rearing of the black vine weevil Otiorhynchus sulcatus
Entomologia Experimentalis Et Applicata, 2004Co-Authors: J R Fisher, Denny J BruckAbstract:The black vine weevil, Otiorhynchus sulcatus (F.) (Coleoptera: Curculionidae) is a univoltine, polyphagous insect that is a nocuous pest of field and container grown ornamentals as well as small fruit crops world-wide (Moorhouse et al., 1992). In the USA, the environmental horticulture industry (floriculture and nursery crops) is the third largest value crop behind corn and soybeans (USDA fact sheets 2001, http://www.nass.usda.gov). Otiorhynchus sulcatus is thought to have a northern European origin and was first recorded in North America in 1835 (Smith, 1932). Oviposition occurs at night with eggs being either dropped on the soil surface or inserted into crevices on plants (Smith, 1932). Early instars begin by feeding on small roots while the later instars feed on larger roots, especially on the phloem and cambium tissues near the soil surface (La Lone & Clarke, 1981). Adults are nocturnal and mainly cause aesthetic damage to plants by notching the leaves. Adults are parthenogenic, so a single individual left unchecked can result in the infestation of an entire nursery. Because of the biology of O. sulcatus , the collection of larvae and adults from the field is very tedious and often requires countless hours of digging through field soil, container-grown plants or searching for adults after dark. Indeed, many chemical and biological control companies developing products for O. sulcatus larval control still rely on searching through infested plant material in order to gather the needed larvae for efficacy studies. Although an artificial diet initially developed by Shorey & Hale (1965) as modified by Shanks & Finnigan (1973) and Shanks (1980) (hereafter referred to as the ‘standard diet’) sustains larvae and is commercially available, there has been no documented technique for continuous mass rearing of O. sulcatus . Studies of weevil biology as well as the development of control strategies require a large, uniform, and predictable supply of insects of all life stages throughout the year. When considering field or potted plants for use in control efficacy or host plant resistant studies, other researchers have often found it useful to store insect eggs for several weeks for subsequent use; many thousands to millions of eggs were needed. The stockpiling of eggs for future use has been necessary with other reared species of Coleoptera (Branson, 1978; Fisher & Edwards, 2002). The egg hatch and viability of the strawberry root weevil, Otiorhynchus ovatus L. were not significantly reduced when it was stored for up to 4 weeks at 4 ° C (Fisher & Edwards, 2002). We have developed a technique for continuous mass rearing of O. sulcatus in the laboratory using a meridic diet. Since small changes in diet composition can often lead to dramatic changes in larval survival and growth, experiments were also performed to determine if O. sulcatus larval survival and development were increased on the improved diet described here, compared to the standard diet. Additionally, we determined if O. sulcatus eggs could be stored for up to 4 weeks at 4 ° C without significant reductions in larval survival and development.
