Canadian Forest Service Publications

Development of a qPCR-based method for counting overwintering spruce budworm (Choristoneura fumiferana) larvae collected during fall surveys and for assessing their natural enemy load: a proof-of-concept study. 2021 Djoumad, A.; Tanguay, P.; Régnière, J; Trudel, G.; Morrison, A.; Fournier, C.; Carleton, D.; Nisole, A.; Stewart, D.; Cusson, M. Laurentian Forestry Centre, Natural Resources Canada. Pest Managment Science. 2022 Jan;78(1):336-343.

Year: 2021

Issued by: Laurentian Forestry Centre

Catalog ID: 40557

Language: English

Availability: PDF (download)

Available from the Journal's Web site.
DOI: 1002

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In eastern Canada, surveys of overwintering 2nd instar spruce budworm (Choristoneura fumiferana) larvae (‘L2s’) are carried out each fall to guide insecticide application decisions in the following spring. These surveys involve the collection of fir and spruce branches in selected stands, followed by the mechanical/chemical removal of larvae. The latter then are counted manually on filter papers, using a stereomicroscope. Considering the significant effort and difficulties which this manual counting entails, we developed a quantitative (q)PCR-based ‘molecular counting’ approach designed to make this step less tedious.