Hostname: page-component-7479d7b7d-c9gpj Total loading time: 0 Render date: 2024-07-11T02:31:18.434Z Has data issue: false hasContentIssue false

APPLICATION OF THE CABBAGE LOOPER EQUIVALENT MODEL TO LEPIDOPTEROUS PESTS OF BRUSSELS SPROUTS IN PRINCE EDWARD ISLAND

Published online by Cambridge University Press:  31 May 2012

Andrew P. Dornan
Affiliation:
Agriculture Canada Research Station, Box 1210, Charlottetown, Prince Edward Island, Canada C1A 7M8
Jeff G. Stewart
Affiliation:
Agriculture Canada Research Station, Box 1210, Charlottetown, Prince Edward Island, Canada C1A 7M8
Mark K. Sears
Affiliation:
Department of Environmental Biology, University of Guelph, Guelph, Ontario, Canada N1G 2W1

Abstract

An investigation into the use of thresholds based on Cabbage Looper Equivalents (CLE) was conducted on Brussels sprouts, Brassica oleracea var. gemmifera (L.), cv. Valiant, grown in Prince Edward Island in 1991 and 1992. The CLE model was used to equate foliage consumption by larvae of the imported cabbageworm, Pieris rapae (L.), the diamondback moth, Plutella xylostella (L.), and the cabbage looper, Trichoplusia ni (Hübner). Management strategies included the following: (1) an untreated check; applications of insecticides after thresholds of (2) 1.0 CLE; (3) 0.50 CLE; or (4) 0.25 CLE per plant were exceeded; (5) bi-weekly applications of insecticides; and (6) applications of insecticides according to the grower’s spray schedule.In 1991, the imported cabbageworm was the most abundant species in the complex attacking the crop and high yields were obtained in all treatments. However, in 1992, the diamondback moth was the principal species and significantly reduced marketable yields in all treatments. Use of CLE as a model for threshold determination in the crop of Brussels sprouts underestimated the potential of the diamondback moth for damage and resulted in improper timing of applications of insecticide for adequate control of the diamondback moth.

Résumé

L’utilisation des seuils établis selon le modèle des équivalents de la Fausse-arpenteuse du chou (modèle CLE) a été testée sur des choux de Bruxelles, Brassica oleracea var. gemmifera (L.) cv. Valiant, cultivés dans l’Île du Prince-Édouard en 1991 et 1992. Le modèle CLE a été utilisé pour évaluer la consommation de feuillage par des larves de Piérides du chou, Pieris rapae (L.), de Fausses-teignes des crucifères, Plutella xylostella (L.), et de Fausses-arpenteuses du chou, Trichoplusia ni (Hübner). Différentes stratégies d’aménagement ont été utilisées : (1) une grille échantillon témoin non traitée; des arrosages d’insecticides après que les seuils de (2) 1,0 CLE, (3) 0,50 CLE, (4) 0,25 CLE par plant aient été dépassés; (5) des arrosages bi-hebdomadaires d’insecticides et (6) des arrosages d’insecticides selon le programme établi par le cultivateur.En 1991, les Piérides du chou représentaient l’espèce la plus abondante parmi les parasites de la culture et tous les traitements ont permis d’obtenir des récoltes abondantes. Cepandant, en 1992, la Fausse-teigne des crucifères était la principale espèce et sa présence a diminué significativement les récoltes utilisables commercialement, quel qu’ait été le traitement utilisé. L’utilisation du modèle CLE pour la détermination des seuils dans le cas du chou de Bruxelles sous-estime les dommages que peut causer la Fausse-teigne des crucifères et résulte en une détermination erronée du moment idéal de l’application d’insecticide pour en assurer le contrôle.

[Traduit par la Rédaction]

Type
Articles
Copyright
Copyright © Entomological Society of Canada 1994

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

Anonymous. 1989. Vegetable Crops. Guide to Cultivar Selection and Chemical Pest Control for the Atlantic Provinces 1989. Advisory Committee on Vegetable Crops. Publication No. 1400a. Agdex No. 250. 51 pp.Google Scholar
Anonymous. 1992. Economic Trends. Results from the 1991 Census of Agriculture. Prince Edward Island Department of Finance. No. 47 Aug. 1992. 15 pp.Google Scholar
Butts, R.A. 1979. Some Aspects of the Biology and Control of Plutella xylostella (L.) (Lepidoptera, Plutellidae) in Southern Ontario. M.Sc. thesis, University of Guelph, Guelph, Ont. 97 pp.Google Scholar
Butts, R.A., and McEwen, F.L.. 1981. Seasonal populations of the diamondback moth, Plutella xylostella (Lepidoptera: Plutellidae), in relation to day-degree accumulation. The Canadian Entomologist 113: 12271231.CrossRefGoogle Scholar
Dornan, A.P. 1993. Economic Thresholds for Lepidopterous Larvae on Cole Crops in Prince Edward Island. M.Sc. thesis, University of Guelph, Guelph, Ont. 129 pp.Google Scholar
Harcourt, D.G., Backs, R., and Cass, L.M.. 1955. Abundance and relative importance of caterpillars attacking cabbage in eastern Ontario. The Canadian Entomologist 87: 400406.CrossRefGoogle Scholar
Hoy, C.W., and Shelton, A.M.. 1987. Feeding response of Artogeia rapae (Lepidoptera: Pieridae) and Trichoplusia ni (Lepidoptera: Noctuidae) to cabbage leaf age. Environmental Entomology 16: 680682.CrossRefGoogle Scholar
MacDonald, M.R. (Ed.). 1989. Instruction Manual for Integrated Pest Management in Onions, Carrots, Lettuce, Celery, and Cole Crops. Ontario Ministry of Agriculture and Food. 105 pp.Google Scholar
Nemato, H., Yano, E., and Kiritani, K.. 1992. Pheromonal control of diamondback moth in the management of crucifer pests. pp. 91–97 in Talekar, N.S. (Ed.), 1992. Management of Diamondback Moth and Other Crucifer Pests: Proceedings of the Second International Workshop. Asian Vegetable Research and Development Centre, Shanhua, Taiwan. 603 pp.Google Scholar
SAS Institute Inc. 1985. SAS Procedures Guide For Personal Computers, Version 6 Edition. SAS Institute Inc., Cary, NC. 373 pp.Google Scholar
Shelton, A.M., Andaloro, J.T., and Barnard, J.. 1982. Effects of cabbage looper, imported cabbageworm, and diamondback moth on fresh market cabbage and processing cabbage. Journal of Economic Entomology 75: 742745.CrossRefGoogle Scholar
Smith, D.B. 1982. The Biology and Management of Plutella xylostella (L.) (Lepidoptera: Plutellidae) in Southern Ontario. M.Sc. thesis, University of Guelph, Guelph, Ont.Google Scholar
Stewart, J.G. 1990. Action Thresholds for Leaf-feeding Insects of Broccoli. Agriculture Canada Canadex. Horticultural Crops. Publication No. 252.521. 1 p.Google Scholar
Stewart, J.G., and Sears, M.K.. 1988. Economic threshold for three species of lepidopterous larvae attacking cauliflower grown in southern Ontario. Journal of Economic Entomology 81: 17261731.CrossRefGoogle Scholar
Theunissen, J., and Sins, A.. 1984. Growth stages of Brassica crops for crop protection purposes. Scientia Horticulturae 24: 111.CrossRefGoogle Scholar
Wit, A.K.H. 1982. The relationship between partial defoliation and yield of Brussels sprouts as a method to assess the quantitative damage induced by leaf eating insects. Zeitschrift für angewandte Entomologie 94: 425431.CrossRefGoogle Scholar