Journal of Economic Entomology (1995) 88, 610-614

S.Y. Li, S.M. Fitzpatrick and M.B. Isman (1995)
Susceptibility of different instars of the obliquebanded leafroller (Lepidoptera: Tortricidae) to Bacillus thuringiensis var. kurstaki
Journal of Economic Entomology 88 (3), 610-614
Abstract: Susceptibility of different instars of the obliquebanded leafroller, Choristoneura rosaceana (Harris), to Bacillus thuringiensis Berliner var. kurstaki was determined in the laboratory by using a leaf dip bioassay. All larval stages were susceptible to B. thuringiensis; fourth and sixth instars were the most and the least sensitive, respectively. A sublethal concentration of B. thuringiensis var. kurstaki had different effects on the development of surviving larvae, depending on the stage treated. Treated first instars weighed significantly less and larval development time was longer than the controls, but pupal weight and adult emergence were not affected. When fifth instars were treated, however, pupal weight and adult emergence were significantly reduced. Treatment with B. thuringiensis var. kurstaki did not affect the adult sex ratio of survivors in experiments with first or fifth instars.
(The abstract is excluded from the Creative Commons licence and has been copied with permission by the publisher.)
Database assignments for author(s): Murray B. Isman, Shiyou Li

Research topic(s) for pests/diseases/weeds:
biocontrol - natural enemies
Research topic(s) for beneficials or antagonists:
general biology - morphology - evolution

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Pest and/or beneficial records:

Beneficial	Pest/Disease/Weed	Crop/Product	Country	Quarant.
	Choristoneura rosaceana	Raspberry/blackberry (Rubus)	Canada (west)
Bacillus thuringiensis var. kurstaki (entomopathogen)	Choristoneura rosaceana