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2. Differential parasitisation of adult and pre-imaginal Coccinella septempunctata (Coleoptera: Coccinellidae) by Dinocampus coccinellae (Hymenoptera: Braconidae)
- Creator:
- Geoghegan, Irene E., Majerus, Tamsin M. O., and Majerus, Michael E. N.
- Type:
- article, model:article, and TEXT
- Subject:
- Braconidae, Coccinellidae, Dinocampus coccinellae, Coccinella septempunctata, host suitability, host recognition, and host instar choice
- Language:
- English
- Description:
- The parasitoid wasp Dinocampus coccinellae has been reported to parasitise adult, pupal and larval coccinellids. Field samples of larvae and pupae of Coccinella septempunctata, collected over 13 years in Britain, have failed to reveal any infected pre-imaginal individuals. The parasitisation rates of D. coccinellae into pre-imaginal and adult C. septempunctata were assessed in both choice and no-choice tests. Observations and test results revealed that British D. coccinellae have a strong preference to oviposit in adult coccinellids rather than larvae or pupae. This preference decreases as wasps age if denied oviposition opportunities.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
3. Phoridae (Diptera) parasitizing Coccinella septempunctata (Coleoptera: Coccinellidae) select older prepupal hosts
- Creator:
- Hurst, Gregory D. D., McMeechan, Fiona K., and Majerus, Michael E. N.
- Type:
- article, model:article, and TEXT
- Subject:
- Host selection, Coccinellidae, Coccinella septempunctata, natural enemies, and Phoridae
- Language:
- English
- Description:
- Phorids parasitizing Coccinella septempunctata, the seven spot ladybird, attend host prepupae and parasitize them at the point of ecdysis to the pupal stage. In this system, oviposition rates would be maximized through the choice of older pre-pupal hosts in preference to young ones. Field study revealed that old pre-pupal hosts were indeed more likely to be attended by phorids than young pre-pupae. We tested the hypothesis that this was due to a preference by simultaneously offering phorids an old and a young prepupal host in a choice test. The results suggest that phorids do indeed distinguish between host prepupae on the basis of age, choosing the older prepupa.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
4. Study of anatomical changes in Coccinella septempunctata (Coleoptera: Coccinellidae) induced by diet and by infection with the larva of Dinocampus coccinellae (Hymenoptera: Braconidae) using magnetic resonance microimaging
- Creator:
- Geoghegan, Irene E., Chudek, John A., Mackay, Regina L., Lowe, Christian, Moritz, Sven, Mcnicol, Ronald J., Birch, A. Nicholas E., Hunter, Geofrey, and Majerus, Michael E. N.
- Type:
- article, model:article, and TEXT
- Subject:
- Coccinella septempunctata, Dinocampus coccinellae, parasitisation, diet, nuclear magnetic resonance (NMR), magnetic resonance microimaging (MRM), relaxation measurement, and T1 and T2
- Language:
- English
- Description:
- A range of nuclear magnetic resonance (NMR) techniques, 1H liquid spectroscopy and T1 and T2 relaxation measurements, and microimaging, have been used to observe changes taking place within the bodies of live samples of Coccinella septempunctata, under a variety of conditions. NMR measurements showed that various organs could be seen and identified. It also showed that by changing the diet of the ladybird from aphids [Acyrthosiphon pisum (Harris)] to a standard artificial diet, major changes took place in the insects' tissues. By using a combination of all three techniques it was concluded that on changing the diet of C. septempunctata a mass of nutrient was built up within the insect's abdomen possibly in the same manner as happens before diapause. Changes in the response to NMR measurements were also seen after infection of C. septempunctata by the parasitoid wasp (Dinocampus coccinellae). Most significantly an image of the parasitoid larva could be seen within the body mass of the ladybird. It was concluded that NMR could become a major tool in the non-destructive study of insects not just as a means of studying anatomy but also to observe changes in the nature of body tissue.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
5. The effect of the coccinellid Harmonia axyridis (Coleoptera: Coccinellidae) on transmission of the fungal pathogen Pandora neoaphidis (Entomophthorales: Entomophthoraceae)
- Creator:
- Wells, Patricia M., Baverstock, Jason, Majerus, Michael E. N., Jiggins, Francis M., Roy, Helen E., and Pell, Judith K.
- Type:
- article, články, model:article, and TEXT
- Subject:
- Zoologie, entomologie, Coccinellidae, Harmonia axyridis, Coccinella septempunctata, multicoloured Asian ladybeetle, harlequin ladybird, seven-spot ladybird, Entomophthorales, Pandora neoaphidis, enhanced transmission, vectoring, 2, and 59
- Language:
- English
- Description:
- The coccinellid Harmonia axyridis is a recent arrival in the UK and is an intraguild predator of the entomopathogenic fungus Pandora neoaphidis. Harmonia axyridis entirely consumes P. neoaphidis-sporulating cadavers and this may have a negative effect on the epizootic potential of P. neoaphidis. Here we assessed within plant transmission, and between plant vectoring, of P. neoaphidis in the presence of either H. axyridis or Coccinella septempunctata, a native coccinellid that only partially consumes fungal cadavers. Transmission was greater in the presence of coccinellids, with 21% of aphids becoming infected with the fungus whilst only 4% were infected in the control. However, there was no significant effect of coccinellid species or sex on fungal transmission. Between plant vectoring occurred infrequently in the presence of both species of coccinellid. The effect of H. axyridis on P. neoaphidis transmission is, therefore, likely to be similar to that of the native coccinellid C. septempunctata. and Patricia M. WELLS, Jason BAVERSTOCK, Michael E.N. MAJERUS, Francis M. JIGGINS, Helen E. ROY, Judith K. PELL.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public