SUSCEPTIBILITY OF LARVAL INSTARS OF SPRUCE BUDWORM, CHORISTONEURA FUMIFERANA (LEPIDOPTERA: TORTRICIDAE), TO BACILLUS THURINGIENSIS
- 1 February 1984
- journal article
- research article
- Published by Cambridge University Press (CUP) in The Canadian Entomologist
- Vol. 116 (2) , 131-137
- https://doi.org/10.4039/ent116131-2
Abstract
Diet incorporation assays detected no difference in susceptibility of instars IV, V, and VI of spruce budworm exposed to Bacillus thuringiensis, either in terms of dose, LC50, or time, LT50. The hypothesis that the dose–response for larvae of each instar fitted a common regression line was statistically acceptable. Differences in the pattern of changes in larval weight of instars IV, V, VI larvae in response to dose were not detected.Small plots were sprayed with 5.5, 10.9, 21.9 BIU/ha at times corresponding to peak instar III, early IV, peak IV, peak V, and peak VI. Instar III larvae were controlled less effectively than were instar IV or V larvae which were controlled equally well. Instar VI larvae were also less effectively controlled than instar IV and V larvae probably because a significant proportion had reached the non-feeding prepupal stage before the full effect of B.t. was obtained.This publication has 6 references indexed in Scilit:
- EFFECT OF EXPOSURE TIME TO BACILLUS THURINGIENSIS ON MORTALITY AND RECOVERY OF THE SPRUCE BUDWORM (LEPIDOPTERA: TORTRICIDAE)The Canadian Entomologist, 1984
- SPECTROPHOTOMETRIC DETERMINATION OF LARVAL INGESTION RATES IN THE SPRUCE BUDWORM (LEPIDOPTERA: TORTRICIDAE)The Canadian Entomologist, 1983
- A 2-YEAR STUDY OF THE EFFICACY OF BACILLUS THURINGIENSIS – CHITINASE COMBINATIONS IN SPRUCE BUDWORM (CHORISTONEURA FUMIFERANA) CONTROLThe Canadian Entomologist, 1976
- Dosage-mortality studies with commercial Bacillus thuringiensis sprayed in a modified Potter's tower against some forest insectsJournal of Invertebrate Pathology, 1973
- Probit AnalysisTechnometrics, 1973
- AN IMPROVED LABORATORY METHOD FOR REARING LARGE NUMBERS OF SPRUCE BUDWORM, CHORISTONEURA FUMIFERANA (LEPIDOPTERA: TORTRICIDAE)The Canadian Entomologist, 1970