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Parasitism of overwintering pupae of cabbage root fly, Delia radicum (L.) (Diptera: Anthomyiidae), in England and Wales

Published online by Cambridge University Press:  10 July 2009

S. Finch
Affiliation:
National Vegetable Research Station, Wellesbourne, Warwick, CV35 9EF, UK
Rosemary H. Collier
Affiliation:
National Vegetable Research Station, Wellesbourne, Warwick, CV35 9EF, UK

Abstract

In populations of overwintering pupae of Delia radicum (L.) collected from ten sites in England and Wales, parasitism varied from 0% at Newcastle to 42% at Evesham. Unlike their hosts, few of the parasites were in extended diapause. Irrespective of when collected at Wellesbourne, emergence of 50% of the ichneumonid parasite Phygadeuon trichops Thoms., the eucoilid parasite Trybliographa rapae (Westw.) and the staphylinid parasite Aleochara bilineata Gylh. occurred after 14, 21 and 28 days, respectively, at 20°C. Early-emerging populations of D. radicum were more heavily parasitised than intermediate- or late-emerging populations. During the winters of 1979–80, 1980–81 and 1981–82, T. rapae and A. bilineata emerged in similar numbers from 37% of the field-collected pupae from Wellesbourne. Less than 1% of the pupae were parasitised by P. trichops. D. radicum adults emerged from a further 25% of the pupae, and the remainder, approximately 38%, were dead. Most dead pupae were recovered from heavily parasitised populations. When parasites were present in high numbers, many of their progeny probably died from multiple parasitism and superparasitism. Comparison with earlier studies indicated that parasitism should be expressed as a percentage of the total pupae, and not just as a percentage of the living insects, if the data are subsequently to be of use for studies on the population dynamics of this pest.

Type
Original Articles
Copyright
Copyright © Cambridge University Press 1984

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References

Abu Yaman, I. K. (1960). Natural control in cabbage root fly populations and influence of chemicals.—Meded. LandbHoogesch. Wageningen 60, 157.Google Scholar
Bromand, B. (1980). Investigations on the biological control of the cabbage root fly (Hylemya brassicae) with Aleochara bilineata.—Bull. SROP 3 (1), 4962.Google Scholar
Coaker, T. H. (1966). The effect of soil insecticides on the predators and parasites of the cabbage root fly (Erioischia brassicae (Bouché)) and on the subsequent damage caused by the pest.—Ann. appl. Biol. 57, 397407.CrossRefGoogle Scholar
Coaker, T. H. & Finch, S. (1971). The cabbage root fly, Erioischia brassicae (Bouché).—Rep. natn. Veg. Res. Stn 1970, 2342.Google Scholar
Collier, R. H. & Finch, S. (1983). Completion of diapause in field populations of the cabbage root fly (Delia radicum).—Ent. exp. appl. 34, 186192.CrossRefGoogle Scholar
De Wilde, J. (1947). De koolvlieg en zijn bestrijding.—Meded. TuinbVoorlDienst no. 45, 70 pp.Google Scholar
El Titi, A. (1980). Die Veränderung der Kohlfliegenmortalität als Folge der chemischen Bekämpfung von anderen Kohlschädlingen.—Z. angew. Ent. 90. 401412.Google Scholar
Finch, S. & Collier, R. H. (1983). Emergence of flies from overwintering populations of cabbage root fly pupae.—Ecol. Entomol. 8, 2936.CrossRefGoogle Scholar
Finch, S. & Skinner, G. (1980). Mortality of overwintering pupae of the cabbage root fly (Delia brassicae).—J. appl. Ecol. 17, 657665.CrossRefGoogle Scholar
Hughes, R. D. (1960). A method of estimating the numbers of cabbage root fly pupae in the soil.—Pl. Path. 9, 1517.CrossRefGoogle Scholar
Hughes, R. D. & Mitchell, B. (1960). The natural mortality of Erioischia brassicae (Bouché) (Dipt., Anthomyiidae): life tables and their interpretation.—J. Anim. Ecol. 29, 359374.CrossRefGoogle Scholar
James, H. C. (1928). On the life-histories and economic status of certain cynipid parasites of dipterous larvae, with descriptions of some new larval forms.—Ann. appl. Biol. 15, 287316.CrossRefGoogle Scholar
Read, D. C. (1962). Notes on the life history of Aleochara bilineata (Gyll.) (Coleoptera: Staphylinidae), and its potential value as a control agent for the cabbage maggot, Hylemya brassicae (Bouché) (Diptera: Anthomyiidae).—Can. Ent. 94, 417424.Google Scholar
Smith, K. M. (1927). A study of Hylemyia (Chortophila) brassicae Bouché, the cabbage root fly and its parasites. with notes on some other Dipterous pests of cruciferous plants.—Ann. appl. Biol. 14, 312330.CrossRefGoogle Scholar
Wadsworth, J. T. (1915). On the life-history of Aleochara bilineata. Gyll., a staphylinid parasite of Chortophila brassicae, Bouché.—J. econ. Biol. 10, 127.Google Scholar
Wishart, G. (1957). Surveys of parasites of Hylemya spp. (Diptera: Anthomyiidae) that attack cruciferous crops in Canada.—Can. Ent. 89. 450454.CrossRefGoogle Scholar
Wishart, G., Colhoun, E. H. & Monteith, A. E. (1957). Parasites of Hylemya spp. (Diptera: Anthomyiidae) that attack cruciferous crops in Europe.—Can. Ent. 89. 510517.Google Scholar
Wishart, G. & Monteith, E. (1954). Trybliographa rapae (Westw.) (Hymenoptera: Cynipidae). a parasite of Hylemya spp. (Diptera: Anthomyiidae).—Can. Ent. 86. 145154.CrossRefGoogle Scholar