title: Onion thrips (Thrips tabaci (Thysanoptera: Thripidae)) in cabbage on Prince Edward Island: observations on planting date and variety choice.
abstract: Onion thrips (Thrips tabaci Lindeman (Thysanoptera: Thripidae)) can be a pest in organic onion production on Prince Edward Island. This study was to examine the effect of planting time and variety on infestation levels and damage by onion thrips on cabbage (Brassicae oleracea capitala (L.)). A field site was planted with 2 main and 8 lesser varieties of cabbage over 4 planting dates. Some varieties were short season and harvested on July 31 with longer season varieties harvested on September 2. Blue sticky traps were used to capture thrips migrating into the field site from July 22-September 2. Traps were counted weekly and cabbage heads within the field site were visually surveyed for thrips. At harvest, heads were weighed and measured, thrips damage was assessed then the head was dissected and thrips counted on the first four layers of the head. Thrips exhibited a preference for Lennox over Bronco throughout the season although thrips populations were not high enough to effect economic damage in 2014. Planting date influenced cabbage head weight and size with later plantings yielding the largest heads. Use of planting date and variety to avoid thrips populations is discussed.
authors: Agriculture and Agri-Food Canada, 32 Main Street, Kentville, NS B4N 1J5 Canada.
authors: Suzanne
authors: S
authors: Blatt
authors: PEI Horticultural Association, 420 University Avenue, Charlottetown, PE C1A 7Z5 Canada.
authors: Andrew
authors: A
authors: Ryan
authors: PEI Horticultural Association, 420 University Avenue, Charlottetown, PE C1A 7Z5 Canada.
authors: Shelley
authors: S
authors: Adams
authors: PEI Horticultural Association, 420 University Avenue, Charlottetown, PE C1A 7Z5 Canada.
authors: Joanne
authors: J
authors: Driscoll
keywords: Cabbage; Onion thrips; Planting time; Prince Edward Island; Variety preference