Rate of Dichlorvos Released from Kill Strips Used in Boll Weevil Eradication Programs

Boll weevil eradication programs equip pheromone traps with kill strips to kill weevils soon after capture and to reduce predation of captured weevils.  Two types of kill strips are used in eradications programs, and both types contain dichlorvos (DDVP) as the active ingredient and are marketed to be effective for up to four weeks.  Consequently, eradication programs typically replace kill strips in traps on a four-week interval.  However, published information regarding the duration of effectiveness of kill strips under field conditions is not available.  We evaluated the weekly rate of DDVP released from two commercially-available kill strips aged in pheromone traps under differing climatic conditions in Texas.  Results of these studies may prove to be of great value for future insecticidal strip management practices or for the development of a more effective dispensing matrix.