Harlekinmariehønens fremmarch i Danmark følges tæt. Både børn og naturinteresserede voksne bidrag... more Harlekinmariehønens fremmarch i Danmark følges tæt. Både børn og naturinteresserede voksne bidrager til kortlægning af artens spredning.
Steenberg, T. & S. Harding: The harlequin ladybird (Harmonia axyridis Pallas) in Denmark; spread ... more Steenberg, T. & S. Harding: The harlequin ladybird (Harmonia axyridis Pallas) in Denmark; spread and phenology during the initial phase of invasion. Ent. Meddr 77: 27-39. Copenhagen, Denmark 2009. ISSN 0013-8851. The harlequin ladybird, Harmonia axyridis (Pallas), is an invasive species new to the Danish insect fauna. A few adult specimens were recorded in 2006. By October 2007 huge numbers
Steenberg, T. & S. Harding: The harlequin ladybird (Harmonia axyridis Pallas) in Denmark; spread ... more Steenberg, T. & S. Harding: The harlequin ladybird (Harmonia axyridis Pallas) in Denmark; spread and phenology during the initial phase of invasion. Ent. Meddr 77: 27-39. Copenhagen, Denmark 2009. ISSN 0013-8851. The harlequin ladybird, Harmonia axyridis (Pallas), is an invasive species new to the Danish insect fauna. A few adult specimens were recorded in 2006. By October 2007 huge numbers of larvae, pupae and adults were found in greater Copenhagen and aggregations of overwintering adults were reported from in- door locations. Through personal observations and records by the public we have mapped the spread and habitat colonization of H. axyridis since October 2007 and have made the first observations on the biology of the species in Denmark. Verified records exist from the southern and eastern part of the country with Hvide Sande as the northernmost location by April 2009, and the species is well established in Copenhagen, in Funen and in South-East Jutland. So far, most records ...
A survey was conducted on confined dairy cattle farms and a pig farm from May–October in 1999 to ... more A survey was conducted on confined dairy cattle farms and a pig farm from May–October in 1999 to determine the activity and relative abundance of pupal parasitoids and the prevalence of entomopathogenic fungi in populations of the haematophagous stable fly, Stomoxys calcitrans (Diptera: Muscidae), in Denmark. Four species of pteromalids were found with Spalangia cameroni as the predominant. The other
Autumn-collected Bembidion lampros and Agonum dorsale were kept outdoors under semi field conditi... more Autumn-collected Bembidion lampros and Agonum dorsale were kept outdoors under semi field conditions to determine winter mortality. On three occasions (autumn, mid-winter and late winter) sub-samples of the population were incubated in the laboratory at room temperature and mortality was recorded. Generally the mortality was low in autumn and mid-winter, not exceeding 5%. A more pronounced post-winter mortality of up to 30% was observed at the end of hibernation. Only a negligible number were infected by the entomopathogenic fungi Beauveria bassiana and Paecilomyces farinosus. Infection experiments with B. bassiana isolates from Sitona lineatus, Tachyporus hypnorum and three species of ground beetles showed a similarly low susceptibility of B. lampros and A. dorsale to B. bassiana and, although Tachyporus spp. showed a distinct mycophagy and a significantly higher mortality, this could not be related to mycosis.
ABSTRACT At one sampling site an entomopathogenic fungus, tentatively identified as Tolypocladium... more ABSTRACT At one sampling site an entomopathogenic fungus, tentatively identified as Tolypocladium cylindrosporum, was found to severely reduce populations of hibernating turnip moth larvae (Agrotis segetum) in consecutive winters, while it was never recorded from other collection sites. It produced cylindrical conidia (5·5 × 2 μm) and smaller, ellipsoidal conidia (3·8 × 2·8 μm) in slimy heads from flask-shaped phialides with thin necks, which occasionally were bent. Phialides were scarce and never occurred in true verticils. Colonies were pale yellow, cottony on artificial medium, with a characteristic mouldy smell. The infectivity of the fungus was tested in a semi-field trial, where suspensions of conidia were applied to hibernating turnip moth larvae in plastic buckets. The experiment also included buckets with larvae and/or soil from the infested site in order to study the natural fungal-induced mortality. The experiment was started in mid-October and buckets were collected four times from January until May. The fungus had caused high mortality by January, when almost 70% of the treated larvae were infected and by March more than 94% of the larvae had been killed. For larvae from the naturally infested site the prevalence was 21% in mid-October and by March it had reached 93%. The ability of the fungus to infect insects at low temperatures may be related to a relatively low optimum temperature for growth of 21 °C, which is lower than for the majority of entomopathogenic hyphomycetes. Host range studies with 10 insect species indicated that the fungus is probably specific to hibernating cutworms.
Harlekinmariehønens fremmarch i Danmark følges tæt. Både børn og naturinteresserede voksne bidrag... more Harlekinmariehønens fremmarch i Danmark følges tæt. Både børn og naturinteresserede voksne bidrager til kortlægning af artens spredning.
Steenberg, T. & S. Harding: The harlequin ladybird (Harmonia axyridis Pallas) in Denmark; spread ... more Steenberg, T. & S. Harding: The harlequin ladybird (Harmonia axyridis Pallas) in Denmark; spread and phenology during the initial phase of invasion. Ent. Meddr 77: 27-39. Copenhagen, Denmark 2009. ISSN 0013-8851. The harlequin ladybird, Harmonia axyridis (Pallas), is an invasive species new to the Danish insect fauna. A few adult specimens were recorded in 2006. By October 2007 huge numbers
Steenberg, T. & S. Harding: The harlequin ladybird (Harmonia axyridis Pallas) in Denmark; spread ... more Steenberg, T. & S. Harding: The harlequin ladybird (Harmonia axyridis Pallas) in Denmark; spread and phenology during the initial phase of invasion. Ent. Meddr 77: 27-39. Copenhagen, Denmark 2009. ISSN 0013-8851. The harlequin ladybird, Harmonia axyridis (Pallas), is an invasive species new to the Danish insect fauna. A few adult specimens were recorded in 2006. By October 2007 huge numbers of larvae, pupae and adults were found in greater Copenhagen and aggregations of overwintering adults were reported from in- door locations. Through personal observations and records by the public we have mapped the spread and habitat colonization of H. axyridis since October 2007 and have made the first observations on the biology of the species in Denmark. Verified records exist from the southern and eastern part of the country with Hvide Sande as the northernmost location by April 2009, and the species is well established in Copenhagen, in Funen and in South-East Jutland. So far, most records ...
A survey was conducted on confined dairy cattle farms and a pig farm from May–October in 1999 to ... more A survey was conducted on confined dairy cattle farms and a pig farm from May–October in 1999 to determine the activity and relative abundance of pupal parasitoids and the prevalence of entomopathogenic fungi in populations of the haematophagous stable fly, Stomoxys calcitrans (Diptera: Muscidae), in Denmark. Four species of pteromalids were found with Spalangia cameroni as the predominant. The other
Autumn-collected Bembidion lampros and Agonum dorsale were kept outdoors under semi field conditi... more Autumn-collected Bembidion lampros and Agonum dorsale were kept outdoors under semi field conditions to determine winter mortality. On three occasions (autumn, mid-winter and late winter) sub-samples of the population were incubated in the laboratory at room temperature and mortality was recorded. Generally the mortality was low in autumn and mid-winter, not exceeding 5%. A more pronounced post-winter mortality of up to 30% was observed at the end of hibernation. Only a negligible number were infected by the entomopathogenic fungi Beauveria bassiana and Paecilomyces farinosus. Infection experiments with B. bassiana isolates from Sitona lineatus, Tachyporus hypnorum and three species of ground beetles showed a similarly low susceptibility of B. lampros and A. dorsale to B. bassiana and, although Tachyporus spp. showed a distinct mycophagy and a significantly higher mortality, this could not be related to mycosis.
ABSTRACT At one sampling site an entomopathogenic fungus, tentatively identified as Tolypocladium... more ABSTRACT At one sampling site an entomopathogenic fungus, tentatively identified as Tolypocladium cylindrosporum, was found to severely reduce populations of hibernating turnip moth larvae (Agrotis segetum) in consecutive winters, while it was never recorded from other collection sites. It produced cylindrical conidia (5·5 × 2 μm) and smaller, ellipsoidal conidia (3·8 × 2·8 μm) in slimy heads from flask-shaped phialides with thin necks, which occasionally were bent. Phialides were scarce and never occurred in true verticils. Colonies were pale yellow, cottony on artificial medium, with a characteristic mouldy smell. The infectivity of the fungus was tested in a semi-field trial, where suspensions of conidia were applied to hibernating turnip moth larvae in plastic buckets. The experiment also included buckets with larvae and/or soil from the infested site in order to study the natural fungal-induced mortality. The experiment was started in mid-October and buckets were collected four times from January until May. The fungus had caused high mortality by January, when almost 70% of the treated larvae were infected and by March more than 94% of the larvae had been killed. For larvae from the naturally infested site the prevalence was 21% in mid-October and by March it had reached 93%. The ability of the fungus to infect insects at low temperatures may be related to a relatively low optimum temperature for growth of 21 °C, which is lower than for the majority of entomopathogenic hyphomycetes. Host range studies with 10 insect species indicated that the fungus is probably specific to hibernating cutworms.
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