The Canadian Entomologist

Articles

EFFECT OF TEMPERATURE ON TOXICITY OF BACILLUS THURINGIENSIS TO THE OBLIQUEBANDED LEAFROLLER (LEPIDOPTERA: TORTRICIDAE)

S.Y. Lia1, S.M. Fitzpatricka1 and M.B. Ismana2

a1 Pacific Agriculture Research Centre, Agriculture and Agri-Food Canada, 6660 NW Marine Drive, Vancouver, British Columbia, Canada V6T 1X2

a2 Department of Plant Science, University of British Columbia, Vancouver, British Columbia, Canada V6T 1Z4

In recent years, the obliquebanded leafroller, Choristoneura rosaceana (Harris) (Lepidoptera: Tortricidae), has become a major pest of raspberries in the Fraser Valley, British Columbia (Anonymous 1994). Overwintering C. rosaceana larvae begin feeding on raspberry leaf buds in early April. Heavy infestation causes serious damage to raspberry plants. Larvae of the first generation hatch in late June to early July, and feed on growth terminals and berries. The occurrence of this generation usually coincides with berry harvesting time. Because the larvae are shaken from the plants by the harvesting machine, C. rosaceana can be a major contaminant of machine-harvested berries.

(Received April 21 1994)

(Accepted January 06 1995)