Transcript Slide 1
Update on Duet™ and insecticide-treated surfaces Sandra A. Allan Center for Medical, Agricultural and Veterinary Entomology ARS/ USDA Gainesville FL DoD Pest Management Workshop Jacksonville NAS February 12 2010 Update 1. Effect of ULV droplets of DUET™ on mosquito (Culex quinquefasciatus) responses 2. Behavioral effects of ULV droplets of DUET™ on the sand fly (Lutzomyia shannoni) 3. Effect of different insecticides on surfaces on landing by mosquitoes and sand flies 1. Effect of ULV droplets of DUET™ on Culex quinquefasciatus responses Duet™ New product Hypothesis Prallethrin contained in Duet enhances flight activity and results in greater mortality Objective Quantify mosquito excitation and mortality caused by Duet and its components applied as an ultra-low-volume aerosol Military Relevance Duet may be a ULV formulation useful for military applications Formulations obtained from Clarke Mosquito Control Treatments Components A B C D E Prallethrin - 1% 1% 1% - Sumithrin 5% - - 5% - Piperonyl butoxide 5% - 5% 5% - + + + + + Inert Ingredients Sprays delivered at a sublethal rate so that behavior can be observed Video recording Individual mosquitoes placed in screened cage in wind tunnel downwind of spray inlet Video recordings were 12.5 min long: pre-spray 5 min Pesticide filters 2.5 min post-spray 5 min 4 ft Door Fan Filters Door air flow * * screened cage with mosquito Side view of wind tunnel Filters Fan o Output spray Intake Pesticide cloud delivery Video Analysis using behavioral analysis software (Observer) Behaviors of individual insects are coded with start and stop times by different keys and data exported to Excel for analysis Event time Assay cage in wind tunnel Event panel Behavior Video Analysis using motion analysis software (Motus) Manual tracking of individual insect produces a flight track and x-and ycoordinates that are exported to Excel for further analysis Resulting flight track Assay cage in wind tunnel Cursor on top of insect ULV Droplet analysis Mosquitoes treated in the wind tunnel were dissected and body parts placed on slides Droplets were measured and counted 50 microns Conclusions Behavior: (pre-spray compared with spray and post-spray) Prallethrin produced increased flight activity (excitation) during spray Sumithrin produced increased flight activity post-spray Controls: no differences in behavior were observed Mortality: Increased mortality appears to be linked to increased activity levels during spray, especially when exposed to treatments with prallethrin Droplets Pre-spray Spray Post-spray Increased flight results in increased droplet contact 2. Behavioral effects of ULV droplets of DUET™ on the sand fly (Lutzomyia shannoni) Objective Quantify sand fly excitation and mortality caused by Duet™ and its components applied as an ULV spray Methods Similar to study with mosquitoes except: Used field-collected Lutzomyia shannoni Smaller assay cages Double screening to contain sand flies Detection of ULV droplets of Duet on body parts % of total droplets 100 Sand flies Mosquitoes 80 60 40 20 50 microns 0 Legs Wings Body Sand fly wing Droplets most detected on wings of sand flies Droplet size distribution – Comparison between sand flies and mosquitoes Mean no./individual 35 Sand flies Mosquitoes 30 25 20 15 10 5 10 microns 0 2.5 5 7.5 10 12.5 15 Sand fly wing Droplet size (um) More small droplets detected on sand flies than on mosquitoes Mortality of sand flies after treatment with Duet formulations in wind tunnel 100 1 hr 24 hr % mortality 80 60 40 Treatments containing prallethrin 20 0 A B C D=Duet E Treatments containing prallethrin had higher mortality at 24 hr Flight tracks of sand flies (Lutzomyia shannoni) exposed to ULV spray of Duet in wind tunnel During spray Sumithrin, PBO + inerts Prallethrin + inerts Prallethrin, PBO + inerts Duet (sumithrin, prallethrin, PBO + inerts) More movement by sand flies exposed to prallethrin Control (inerts) Conclusions Similar to mosquitoes, sand fly activity and mortality is enhanced in the presence of prallethrin 3. Effect of different insecticides on surfaces on landing by mosquitoes and sand flies If given a choice, will mosquitoes land on surfaces treated with residual pesticides? Are there differences between mosquitoes and sand flies? Objective To compare landing of mosquitoes and sand flies on surfaces treated with different residual pesticides Military Relevance To identify the most effective available residual pesticides for control of mosquitoes and sand flies Methods Selected residual insecticides approved for application on vegetation and other surfaces for mosquito control Applied to surfaces at maximum label rate Active ingredient Formulation AI (%) Bifenthrin Cyfluthrin Deltamethrin Permethrin Lambda-cyhalothrin Talstar One Tempo Ultra (SC) Suspend SC Dragnet Triazicide 7.9 11.8 4.75 36.8 0.002% Methods Species Aedes albopictus (lab-reared) Lutzomyia shannoni (field-collected) Phlebotomus papatasi (lab-reared) Approach Each test cage with: Filter paper Wax myrtle leaves Treated surface Control surface Methods – Mosquito videotaping Assay cage Camera Methods – Sand fly videotaping Camera Assay cage Preliminary Conclusions Mosquitoes were more sensitive than sand flies to pesticide-treated substrates Repellent responses were stronger to treated filter paper than to treated leaves which likely reflects a higher dose on the filter paper Landing responses were least affected by lambdacyhalothrin and most decreased by permethrin Acknowledgements CMAVE Gary Clark Erin Vrzal Fran Ellison Larry Pitts Eric Paulsen Lee Cohnstaedt Miriam Cooperband (USDA/APHIS) William Jany, Clarke Mosquito Control This study was supported in part by funds from the Deployed War-Fighter Protection Research Program from the U.S. Department of Defense through the Armed Forces Pest Management Board to the Agricultural Research Service of the U.S. Department of Agriculture.