Hostname: page-component-586b7cd67f-dlnhk Total loading time: 0 Render date: 2024-11-24T03:11:38.151Z Has data issue: false hasContentIssue false
  • English
  • Français

Development of Gryon gnidus (Nixon) (Hymenoptera: Scelionidae) in eggs of Acanthomia tomentosicollis (Stål) (Hemiptera: Coreidae) killed either by gamma irradiation or by freezing

Published online by Cambridge University Press:  10 July 2009

R. I. Egwuatu  and
T. Ajibola Taylor
R. I. Egwuatu
Affiliation:
Legume Entomology Research Unit, Department of Agricultural Biology, University of lbadan, Ibadan, Nigeria
T. Ajibola Taylor
Affiliation:
Legume Entomology Research Unit, Department of Agricultural Biology, University of lbadan, Ibadan, Nigeria
Get access Rights & Permissions [Opens in a new window]

Abstract

Abstract

The effects of host quality on the development of Gryon gnidus (Nixon), a scelionid egg-parasite of Acanthomia tomentosicollis (Stål), are reported. A minimum exposure period of 24 h at —4°C or an irradiation dose of 1000 rads from a cobalt-60 source killed 98–99% of freshly-deposited, fertile eggs of A. tomentosicollis. Sub-lethal periods of exposure delayed hatching in both treatments and the incubation period was increased from 4 days to 5–7 days in eggs exposed to freezing temperature and 4–7 days in irradiated eggs. About 44% of the fertile, untreated eggs hatched normally while 56% were parasitised by G. gnidus. The irradiated or frozen eggs did not hatch and were not parasitised by G. gnidus, thus indicating that G. gnidus would not parasitise dead eggs of A. tomentosicollis. The significance of these results is discussed.

Type
Original Articles
Information
Bulletin of Entomological Research , Volume 67 , Issue 1 , March 1977 , pp. 31 - 33
Copyright
Copyright © Cambridge University Press 1977

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Clausen, C. P.. (1940). Entomophagous insects. — 688 pp. London, McGraw-Hill.Google Scholar
Egwuatu, R. I.. (1975). Studies on the bionomics of Acanthomia tomentosicollis (Stal) (Hemiptera, Coreidae) and its egg–parasite, Gryon gnidus (Nixon) (Hymenoptera, Scelionidae). — Ph.D. Thesis, University of Ibadan, Nigeria.Google Scholar
Le Pelley, R. H.. (1968). Pests of coffee. — 590 pp. London, Longmans.Google Scholar
Lewis, W. J.. & Young, J. R.. (1972). Parasitism by Trichogramma evanescens of eggs from tepa-sterilized and normal Heliothis zea. — J. econ. Ent. 65, 705–708.CrossRefGoogle Scholar
Materu, M. E. A.. (1968). The biology and bionomics of Acanthomia tomentosicollis (Stål) and A. horrida (Germ.) (Coreidae, Hemiptera ) in Arusha area of Tanzania. — Ph.D. Thesis, University of East Africa, Nairobi, Kenya.Google Scholar
Materu, M. E. A.. (1970). Damage caused by Acanthomia tomentosicollis (Stål) and A. horrida (Germ.) (Hemiptera, Coreidae). — E. Afr. agric. For. J. 35, 429–435.Google Scholar
Materu, M. E. A.. (1971). Population dynamics of Acanthomia spp. (Hemiptera Coreidae) on beans and pigeon peas in the Arusha area of Tanzania. — E. Afr. agric. For. J. 36, 361–383.CrossRefGoogle Scholar
Taylor, T. A.. (1975). Gryon gnidus, a scelionid egg-parasite of Acanthomia tomentosicollis (Hem.: Coreidae) in Nigeria. — Entomophaga. 20, 129–134.CrossRefGoogle Scholar
Taylor, T. A.. & Omoniyi, O.. (1970). Variation in number of micropyles in eggs of Acanthomia tomentosicollis (Stål) (Hemiptera, Coeridae). — Nigerian Ent Mag. 2 70–73.Google Scholar