Economic thresholds for the management of imported cabbageworm, Pieris rapae (L.), diamondback moth, Plutella xylostella (L.), larvae, and cabbage looper, Tricoplusia ni (Hübner), on cabbage, Brassica oleracea L., were evaluated at Bouctouche, New Brunswick, Canada, in 1992, 1993,and 1995. Six treatments were tested in 1992:an untreated control; a weekly application of insecticide after insects appeared; a weekly application of insecticide after heading; and an insecticide application when thresholds of 0.25, 0.50, or 1.0 cabbage looper equivalent per plant per week were reached. Eight treatments were tested in 1993and 1995:an untreated control; a biweekly application of insecticide when insects appeared; a biweekly application of insecticide after heading; and an insecticide application when thresholds of 0.10, 0.15, 0.20, 0.25, or 0.50 cabbage looper equivalent per plant per week were reached. Generally, on average, for similar marketable yields, plots using the 0.10 cabbage looper equivalent threshold needed 3 fewer insecticide applications compared with plots treated biweekly after insects appeared. In 1995,revenues for the 0.10 cabbage looper equivalent threshold treatment were 9.49 per hectare greater than those for the biweekly treatments beginning after insects appeared.
Document Type: Research Article
Publication date: June 1, 1998
More about this publication?
Journal of Economic Entomology is published bimonthly in February, April, June, August, October, and December. The journal publishes articles on the economic significance of insects and is divided into the following sections: apiculture & social insects; arthropods in relation to plant disease; forum; insecticide resistance and resistance management; ecotoxicology; biological and microbial control; ecology and behavior; sampling and biostatistics; household and structural insects; medical entomology; molecular entomology; veterinary entomology; forest entomology; horticultural entomology; field and forage crops, and small grains; stored-product; commodity treatment and quarantine entomology; and plant resistance. In addition to research papers, Journal of Economic Entomology publishes Letters to the Editor, interpretive articles in a Forum section, Short Communications, Rapid Communications, and Book Reviews.