Tuesday, November 16, 2004
D0411

Seasonal abundance and control of eastern flower thrips, Frankliniella tritici (Thysanoptera: Thripidae), in blackberry in Arkansas

Barbara Lewis, balewis@uark.edu, Donn T. Johnson, dtjohnso@uark.edu, Joe Williamson, jrwilli@uark.edu, and Jacquelyn A. McKern, jmckern@uark.edu. University of Arkansas, Entomology, 319 Agriculture Building, Fayetteville, AR

Eastern flower thrips are reported to immigrate on spring weather systems to much of the east central U.S. during the blackberry bloom period. Feeding on fruit by high populations of eastern flower thrips may contribute to the formation of white drupes on the Apache blackberry fruit and reduce quality of raspberry fruit. Seasonal abundance of thrips were derived from weekly counts of thrips were recorded from blue sticky cards placed in a blackberry field in Judsonia, Arkansas. The thrips count per blue sticky card peaked by mid to late May in 2003 and 2004. In an efficacy study in 2004, foliar sprays were applied on 20 May and 1 June to Apache blackberry plants at rate of 100 gal. per acre. Thiacloprid (Calypso), spinosad (SpinTor), thiamethoxam (Actara), indoxacarb (Avaunt), Novaluron, and GF968 all significantly reduced the mean number of thrips on 20 blackberry fruit clusters sampled per 10 plant plots (four replicates) compared to untreated plants.


Keywords: control, abundance