Submitted to: Journal of Economic Entomology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: September 1, 2002
Publication Date: April 1, 2003
Citation: SUH, C.P., SPURGEON, D.W., HAGOOD, S. EVALUATION OF KILL STRIPS ON BOLL WEEVIL (COLEOPTERA: CURCULIONIDAE) MORTALITY IN PHEROMONE TRAPS AND IMPACT ON WEEVIL ESCAPE. JOURNAL OF ECONOMIC ENTOMOLOGY. 2003. 96(2):348-351. Interpretive Summary: Boll weevil eradication programs typically equip insect traps with a plastic strip containing an insecticide (kill strip). The kill strips are intended to kill weevils soon after capture, presumably reducing the incidence of weevils escaping from traps. Despite their widespread use, there is no scientific documentation of the effectiveness of kill strips in terms of killing weevils in traps and reducing the incidence of escapes. We tested two commercially available kill strips, one of which is currently used by the Texas Boll Weevil Eradication Foundation, and found that both types of kill strips killed >90% of weevils after several days of exposure. Additionally, we found that as many weevils escaped from traps with kill strips as from those without kill strips, with most escapes occurring within the first hour after weevils were captured. Because >90% of escapes occurred within the first hour after weevils were captured and <3% of weevils died during the first hour of exposure to kill strips in traps, kill strips did not reduce the incidence of weevils escaping from traps. Consequently, the use of kill strips in large-scale boll weevil management programs is not justified on the basis of reduced weevil escape.
Technical Abstract: A field study was conducted to examine the temporal patterns of boll weevil mortality provided by two commercially available kill strips, Hercon VaporTape II and Plato Insecticide Strip, and to evaluate the impacts of these devices on weevil escape from traps. Both types of kill strips produced similar levels of weevil mortality with the exception of the last two inspection intervals (30 and 46 h following continual exposure to kill strips). At these intervals, the Plato Strip produced significantly higher mortality than the Hercon strip; however, these differences were numerically small (10 and 6%, respectively). Both types of kill strips produced a high level of weevil mortality in traps (>90%), but at a relatively slow rate. On average, 5 to 8% of weevils escaped from traps whether a kill strip was present or absent. A strong temporal pattern of escape was observed, with >90% of escape occurring within the first hour after weevils were introduced into traps. Because >90% of escape occurred within the first hour weevils were in the traps and <3% of weevils died during the first hour of exposure to kill strips in traps, use of kill strips in large scale boll weevil management programs is not justified of the basis of reduced weevil escape.