Hostname: page-component-848d4c4894-4rdrl Total loading time: 0 Render date: 2024-06-21T18:38:41.921Z Has data issue: false hasContentIssue false
  • English
  • Français

RELIABILITY OF DEGREE-DAY INDICES FOR PREDICTING SPRING EMERGENCE OF THE SPOTTED TENTIFORM LEAFMINER, PHYLLONORYCTER BLANCARDELLA (LEPIDOPTERA: GRACILLARIIDAE), IN ONTARIO

Published online by Cambridge University Press:  31 May 2012

R. M. Trimble
R. M. Trimble
Affiliation:
Research Station, Agriculture Canada, Vineland Station, Ontario L0R 2E0
Get access Rights & Permissions [Opens in a new window]

Abstract

The validity of using 40 ± 12 degree-days (DD) above 6.7 °C summed from 1 April for predicting first spring emergence of the spotted tentiform leafminer, Phyllonorycter blancardella (Fabr.), was tested. In Ontario's major apple growing areas from 1978 to 1981, the observed day of first emergence occurred 12–45 days before the predicted day. Reasons for this inaccuracy are discussed.

An alternative method, summing DDs from 1 March above a base temperature of 5.5 °C, was also tested using three methods of computation. The number of DDs accumulated to the day of first emergence and to the day of 50% cumulative emergence varied greatly between years at one location and between locations during one year. This variation is likely due to a variable relationship between air temperature and temperature in the leafminer's habitat. It is suggested that a more accurate predictive index could be developed through an understanding of the relationship between habitat temperature and weather factors such as air temperature, insolation, and snow cover.

Résumé

On a vérifié le bien-fondé d'utiliser 40 ± 12 degrés-jours (DD) au delà de 6.7 °C (additionnés à partir du 1er avril) pour prédire la première apparition printanière de la mineuse du pommier, Phyllonorycter blancardella (Fabr.). Dans les principales régions productrices de l'Ontario de 1978 à 1981, la date de la première émergence survient 12 à 45 jours avant la date prévue. L'auteur examine les raisons de cet écart.

On a également vérifié une autre méthode qui consiste à additionner les DD au delà d'une température seuil de 5.5 °C à compter du 1er mars, au moyen de trois techniques de calcul. Le nombre de DD accumulés à la date de première sortie et à celle de 50% d'émergence cumulative varie considérablement d'une année à l'autre à un endroit et d'un endroit à l'autre au cours d'une même année. Cette variation est probablement due à la variabilité du rapport entre la température de l'air et celle de l'habitat de la mineuse. Il semblerait possible d'établir un indice prévisionnel plus précis par une meilleure compréhension de la relation qui existe entre la température de l'habitat et certains facteurs météorologiques comme la température de l'air, l'insolation et la couverture de neige.

Type
Articles
Information
The Canadian Entomologist , Volume 115 , Issue 4 , April 1983 , pp. 393 - 398
Copyright
Copyright © Entomological Society of Canada 1983

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. 1973. Temperature and precipitation 1941–1970. Ontario. Atmospheric Environment, Environment Canada.Google Scholar
Baker, C. R. B. 1980. Some problems in using meteorological data to forecast the timing of insect life cycles. EPPO Bull. 10: 83–91.Google Scholar
Baker, C. R. B. 1981. Accumulated temperatures in some pest habitats in 1976–78. Agric. Meteorol. 23: 245–253.CrossRefGoogle Scholar
Baker, C. R. B. and Miller, G. W.. 1978. The effect of temperature on the postdiapause development of four geographical populations of the European cherry fruit fly (Rhagoletis cerasi). Entomologia exp. appl. 23: 1–13.CrossRefGoogle Scholar
Baskerville, G. L. and Emin, P.. 1969. Rapid estimation of heat accumulation from maximum and minimum temperatures. Ecology 50: 514–517.Google Scholar
Boller, E. F. and Bush, G. L.. 1974. Evidence for genetic variation in populations of the European cherry fruit fly, Rhagoletis cerasi (Diptera: Tephritidae) based on physiological parameters and hybridization experiments. Entomologia exp. appl. 17: 279–293.CrossRefGoogle Scholar
Hagley, E. A. C., Trottier, R., Herne, D. H. C., Hikichi, A., and Maitland, A.. 1980. Pest management in Ontario apple orchards. Research Branch, Canada Agriculture, Ottawa, Ontario.Google Scholar
Johnson, E. F. 1975. Influence of temperature on development of Lithocolletis blancardella Fabricius and Apanteles ornigis Weed. M.Sc. Thesis, University of Guelph.Google Scholar
Johnson, E. F., Trottier, R., and Laing, J. E.. 1979. Degree-day relationships to the development of Lithocolletis blancardella (Lepidoptera: Gracillariidae) and its parasite Apanteles ornigis (Hymenoptera: Braconidae). Can. Ent. 111: 1177–1184.Google Scholar
Trimble, R. M. 1983. Diapause termination and the thermal requirements for postdiapause development in six Ontario populations of the spotted tentiform leafminer, Phyllonorycter blancardella (Lepidoptera: Gracillariidae). Can. Ent. 115: 387–392.Google Scholar
Trottier, R. 1980. Early warning system for apple pest management in Ontario. EPPO Bull. 10: 253–257.Google Scholar
Trottier, R. and Herne, D. H. C.. 1979. Temperature relationships to forecast hatching of overwintered eggs of the European red mite, Panonychus ulmi (Acarina: Tetranychidae). Proc. ent. Soc. Ont. 110: 53–60.Google Scholar