Distributions and interactions of the stem miners Psylliodes chrysocephala and Ceutorhynchus pallidactylus and their parasitoids in a crop of winter oilseed rape (Brassica napus)

A - Papers appearing in refereed journals

Ferguson, A. W., Barari, H., Warner, D. J., Campbell, J. M., Smith, E. T., Watts, N. P. and Williams, I. H. 2006. Distributions and interactions of the stem miners Psylliodes chrysocephala and Ceutorhynchus pallidactylus and their parasitoids in a crop of winter oilseed rape (Brassica napus). Entomologia Experimentalis et Applicata. 119 (2), pp. 81-92.

AuthorsFerguson, A. W., Barari, H., Warner, D. J., Campbell, J. M., Smith, E. T., Watts, N. P. and Williams, I. H.
Abstract

The within-field spatio-temporal distributions and relationships of two pest insects with stem-mining larvae, Psylliodes chrysocephala (L.) (Coleoptera: Chrysomelidae) and Ceutorhynchus pallidactylus (Marsham) (Coleoptera: Curculionidae), and their larval endoparasitoids, Tersilochus microgaster (Szepligeti) and Tersilochus obscurator Aubert (Hymenoptera: Ichneumonidae), respectively, were studied in a crop of winter oilseed rape [Brassica napus L. (Brassicaceae)]. The insects were sampled, at different life stages, at 40 spatially referenced points within the oilseed rape in 1998-99 and in the following crop of winter wheat. Distributions were analysed and compared using SADIE (Spatial Analysis by Distance IndicEs) and by tests of edge distribution. Tersilochus microgaster emerged from overwintering by the end of March and T. obscurator from mid April to mid May 2000. Tersilochus microgaster parasitized 10.8% of P. chrysocephala larvae, peak parasitism occurring in May. The distribution of each species was patchy and irregular. Psylliodes chrysocephala and its parasitoid were closely associated, but new generation C. pallidactylus and T. obscurator were less so, probably because of host mortality caused by the parasitoid. The two host-parasitoid pairs showed distributions that were polarized with respect to each other. The genesis of these spatial patterns is discussed in relation to the influence of wind direction, plant size, and interspecific interactions. The potential of these parasitoids as biocontrol agents in integrated pest management is discussed. Opportunities for conservation biocontrol in oilseed rape offered by spatio-temporal targeting of insecticides to avoid parasitoids and by reduced soil tillage are examined.

KeywordsEntomology
Year of Publication2006
JournalEntomologia Experimentalis et Applicata
Journal citation119 (2), pp. 81-92
Digital Object Identifier (DOI)doi:10.1111/j.1570-7458.2006.00404.x
Open accessPublished as non-open access
Funder project or code509
Project: 4308
Oilseed rape crop ecology:optimising crop husbandry for conservation biological control and greater biodiversity
Integrated pest management strategies incorporating bio-control for European oilseed rape pests (MASTER)
ISSN00138703
0013-8703
PublisherWiley

Permalink - https://repository.rothamsted.ac.uk/item/89964/distributions-and-interactions-of-the-stem-miners-psylliodes-chrysocephala-and-ceutorhynchus-pallidactylus-and-their-parasitoids-in-a-crop-of-winter-oilseed-rape-brassica-napus

22 total views
0 total downloads
1 views this month
0 downloads this month