Efficacy and mode of action of female-equivalent dispensers of pheromone for mating disruption of codling moth

Transcription

1 Agriculturl nd Forest Entomology (28), 1, DOI: /j x Efficcy nd mode of ction of femle-equivlent dispensers of pheromone for mting disruption of codling moth L. L. Stelinski, P. McGhee *, M. Grieshop *,, J. Brunner nd L. J. Gut * Entomology nd Nemtology Deprtment, Citrus Reserch nd Eduction Center, University of Florid, Lke Alfred, FL 3385 nd * Deprtment of Entomology, Michign Stte University, Est Lnsing, MI nd Tree Fruit Reserch nd Extension Center, Wshington Stte University, Wentchee, WA 9881, U.S.A. Astrct 1 We evluted the efficcy nd mode of ction of commercilly ville femleequivlent dispensers of pheromone for mting disruption of codling moth Cydi pomonell (L.) (Lepidopter Tortricide). 2 Scentry fires, ut not Hercon flkes, were consistently s or more effective thn Isomte C Plus dispensers when pplied y hnd t 5 dispensers per tree. 3 Individul Scentry fires were slightly more ttrctive to mle codling moth thn Hercon flkes. 4 Efficcy of erilly pplied Scentry fires ws equivlent to tht of Isomte dispensers in disrupting mle codling moth in 4-h commercil pple plots. 5 Initil deposition nd retention of erilly pplied fires were inefficient with pproximtely 44% formultion loss t ppliction, poor rinfstness nd grdul loss of dispensers from tree cnopies fter ppliction. 6 Mle codling moths were cptured in trps ited with lures contining.1 mg of pheromone nd mted with tethered virgin femles tht were surrounded y eight fires plced 3 cm wy or 16 fires plced 45 cm wy in untreted plots nd plots treted with ckground of 5 Isomte dispensers per hectre. 7 A plusile explntion for mting disruption of codling moth y femleequivlent dispensers is competitive ttrction without ssocited hitution nd thus improving the effectiveness of these technologies will depend on mximizing the ttrctiveness of individul dispensers s well s the ppliction density of dispensers per re of crop. Keywords Cydi pomonell, fires, flkes, reservoir dispensers, Tortricide. Introduction The codling moth Cydi pomonell (L.) (Lepidopter Tortricide) is one of the leding pests driving the reserch nd development progrmmes of the glol semiochemicl industry with pproximtely 162 h of pome fruit treted with synthetic formultions of pheromone for codling moth worldwide ( Witztgll et l., 28 ). Susequent to its registrtion in the U.S.A. in 1991, the polyethylene Isomte reservoir dispenser hs ecome n industry stndrd ( Thomson et l., 1999; Witztgll et l., 28 ). Such dispensers contin pproximtely 2 mg of three-component codling moth pheromone lend nd re deployed y hnd once per seson t densities of 5 1 units/h. Effectiveness of Isomte dispensers hs een vrile ( Crdé & Minks, 1995; Witztgll Correspondence: Luksz Stelinski. Tel: ; fx: ; e-mil: stelinski@ufl.edu et l., 28 ); however, re-wide pplictions hve een successful nd hve reduced relince on rod-spectrum insecticides ( Wldner, 1997; Brunner et l., 22 ). The min drwcks of reservoir dispenser technology re the need for hnd ppliction nd the economic limittion of point source density of pproximtely 1 units/h, which typiclly results in only one or two dispensers per tree ( Epstein et l., 26 ). Severl technologies hve een investigted s possile lterntives to reservoir dispensers for mting disruption of codling moth. Microencpsulted formultions of pheromones re deployed with stndrd griculturl ir-lst spryers, replcing the need for hnd ppliction. Although such spryle formultions re highly desirle from prcticl stndpoint, their efficcy hs een inconsistent nd short-lived in the field ( Epstein et l., 23; Knight & Lrsen, 24 ). A recently developed low volume ppliction method, which yields high densities of clusters comprised Journl compiltion 28 The Royl Entomologicl Society

2 39 L. L. Stelinski et l. of hundreds of microcpsules on tree folige, hs improved efficcy nd incresed longevity of spryle formultions for codling moth ( Knight & Lrsen, 24 ). Another lterntive to reservoir dispensers re erosol devices. These re deployed t very low densities (pproximtely 2 3) per hectre of crop ( Knight, 24 ). Current erosol devices re mechnized nd remotely-controlled delivering metered sprys of solvent-diluted pheromone t regulr intervls ( Knight, 24 ). Initil tests with codling moth demonstrted high efficcy (95 98% disruption) y deploying 2.3 erosol devices per hectre of wlnut ( Shorey & Gerer, 1996 ). However, more recent investigtion of commercilly ville erosol devices deployed t 2.5 units/h of pples reported poor efficcy of codling moth disruption (24 75%) ( Stelinski et l., 27 ). Femle-equivlent dispensers represent third lterntive to hnd-pplied reservoir dispensers. These include Hercon Disrupt CM flkes (Hercon, Emigsville, Pennsylvni) nd Scentry NoMte CM fires (Scentry, Billings, Montn) ( Swenson & Wetherston, 1989 ). These dispensers re lso mchine-pplied to crops ut s tens of thousnds of point sources of pheromone per hectre of crop. They re pplied vi custom pplictors nd re mendle to eril ppliction. The presumle dvntges of these technologies re mchine ppliction nd deployment of mny thousnds of point source per hectre. Incresing point source density ove 1 dispensers per hectre hs een shown to improve codling moth disruption ( Epstein et l., 26; Stelinski et l., 26; Angeli et l., 27 ). A proof-of-concept investigtion of n erly hollow fire dispenser (Conrel), deployed s 17 points of ten fires/h, lso showed excellent disruption (96 1%) of codling moth ( Crdé et l., 1977 ). In the present study, we evluted the efficcy nd mode of ction of commercilly ville femle-equivlent dispenser formultions for mting disruption of codling moth. The specific ojectives were: (i) to compre the efficcies of two commercilly ville femle-equivlent dispenser formultions with the industry stndrd reservoir dispenser formultion; (ii) to investigte the efficcy, pttern of deposition within the crop, nd longevity of dherence of n erilly pplied, femle-equivlent dispenser formultion; (iii) to determine the ttrctiveness of individul nd clusters of femle-equivlent dispensers reltive to monitoring lures; (iv) to determine the effect of fire density on the ttrctiveness of centrlly mounted monitoring trp or virgin femle; nd (v) to determine the effect of fire distnce wy from monitoring trp or virgin femle on disruption of mle codling moths orienting to the trp or femle. Mterils nd methods Pheromone formultions Isomte C Plus dispensers (Pcific Biocontrol Co., Vncouver, Wshington) were reported to contin 25 mg of 53.% codlemone [( E, E )-8,1-dodecdien-1-ol], 29.7% 12OH, 6.% 14OH nd 11.3% inert ingredients per dispenser with recommended ppliction rte of 5 1 units/h. The Scentry fier formultion contined 1.8% codlemone nd 89.2% inert ingredients (pproxitely 26 g of codlemone/fire) with recommended ppliction rte of g of fires/h. The Hercon flke formultion contined 5.97% codlemone nd 94.3% inert ingredients (pproximtely 19 g of codlemone/flke) with recommended ppliction rte of 827 g of flkes/h. Smll plot comprison of hnd-pplied femleequivlent dispensers with hnd-pplied reservoir dispensers This experiment compred the effectiveness of hnd-pplied femle-equivlent dispensers with hnd-pplied reservoir dispensers in disrupting sexul communiction of codling moth in experimentl orchrd plots. It ws conducted t the Trevor Nichols Reserch Complex (TNRC) of Michign Stte University in Fennville, Michign. in 4-h orchrd of 2-yer-old Delicious pple trees, pproximtely 2 3 m tll. Trees were plnted in 3 6 m tree/row spcing. Orchrd plots were mintined with stndrd fungicide nd fertilizer tretments ut did not receive pplictions of insecticides. The tretments compred were: (i) two Isomte C Plus dispensers per tree (pproximtely 815 per hectre); (ii) 5 Scentry fires/tree (pproximtely per hectre); (iii) 5 Hercon flkes per tree (pproximtely per hectre); nd (iv) no pheromone control. Femle-equivlent dispensers were pplied t 5 per tree sed on previous reserch showing this to e n effective density ( Epstein et l., 26 ). Isomte dispensers were ttched to tree rnches in the upper portions of the tree cnopy. Likewise, oth fires nd flkes were hnd-pplied to rnches nd leves in the upper portions of tree cnopies. Applictions were mde y first completely sumerging either fires or flkes in Bio-Tk (Scentry Biologicls Inc., Buckeye, Arizon), n dhesive sticker dditive tht is pplied with Scentry fires for dhesion to folige, nd then crefully plcing the fire or flke flt ginst the surfce of tree leves or stems using lortory forceps. Fires nd flkes were pplied in this fshion so s to promote retention of pplied dispensers. The experimentl design ws rndomized complete lock with four.4-h (nine tree) replictes per tretment. Tretments were seprted y 54-m uffers. Tretments were monitored with pheromone-ited delt trps (LPD Scenturin Gurdpost; Suterr, Bend, Oregon) ited with Suterr CM 1X (1 mg of codlemone) red septum lures. Ech plot received totl of five trps, with one trp plced in the centrl tree nd the other trp plced on the interior portion of ech corner tree. Trps were hung pproximtely 2 3 m ove ground level in the upper third of the tree cnopy. Trps were positioned s fr wy s possile from pheromone dispensers (t lest 6 cm). Moths cptured in trps were counted nd removed weekly. The experiment ws conducted from 27 My to 23 July 24. Lrge plot comprison of erilly pplied Scentry fires with hnd-pplied Isomte C Plus This experiment compred the effectiveness of erilly pplied Scentry fires with hnd-pplied Isomte C Plus in Journl compiltion 28 The Royl Entomologicl Society, Agriculturl nd Forest Entomology, 1,

3 Femle-equivlent dispensers for disruption of codling moth 391 disrupting codling moth in commercil pple orchrd plots in Grnd Rpids, Michign. Orchrds were plnted on m tree/row spcing (441 trees per hectre) nd with m tll Delicious pples. Replicte plots were 4 h in size nd were spced y.5 h uffers t minimum. The tretments compred were: (i) Isomte C Plus t 1 dispensers/h; (ii) erilly pplied fires t 16 g/h (pproximtely fires/h); nd (iii) no pheromone control. Isomte C Plus ws pplied y hnd to the upper third of the tree cnopies. Fires were pplied from fixed wing ircrft equipped with Ecogen eril ppliction pods (Ecogen Inc., Goodyer, Arizon), which is specificlly designed for the ppliction of griculturl products. The pods dispense clirted mount of product from centrl hopper contining oth fires nd Bio-Tk dhesive into spinning cone tht distriutes fires onto the crop. Fires were dispensed with 2.3 L of Bio-Tk dhesive per hectre. An ppliction of fires ws mde t the eginnings of oth the first (5 6 My 24) nd second (12 13 July 24) genertion codling moth flights. The experimentl design ws rndomized complete lock with four replictes per tretment. All plots on ech frm were lso treted with identicl insecticide progrmmes to prevent uncceptle levels of fruit dmge t hrvest. During the first genertion, there were two pplictions of zinphos-methyl t 2.2 kg/h nd during the second genertion there were two pplictions of thiocloprid t.43 L/h. Disruption ws evluted with ten pheromone trps ited with Trécé CM L2 (3 mg of codlemone) lures (Trécé, Adir, Oklhom) deployed per plot. Trps were plced in plots t lest 15.2 m wy from plot orders nd spced y t lest 6 m wy from ech other. Mid-seson nd hrvest ssessments of fruit injury were conducted y evluting 3 rndomly-selected fruit (15 high nd 15 low in the cnopy) from ech of 2 rndomly-selected trees per plot. The experiment ws conducted from 12 My to 2 July 24. Deposition of erilly pplied fires The pttern of fire deposition ws quntified during the two eril pplictions of fires mde to the four 4-h commercil pple orchrd plots descried ove. Thirty white crdord pnels (.4 m 2 ) were distriuted within ech orchrd immeditely prior to ppliction. Ten pnels were plced on the ground in ech of three loctions: (i) etween trees in row; (ii) etween rows; nd (iii) under tree cnopies. The numer of fires dhering to pnels in ech loction ws ssessed immeditely fter eril ppliction. Bsed on the men numers of fires counted on the pnels t ech loction, the numer of fires dhering to ech tree ws estimted using the formul: (89 91 fires pplied per hectre estimted numer of fires lnding etween tree cnopies estimted numer of fires lnding under trees per hectre)/441 trees per hectre. Retention of erilly pplied fires After ech eril ppliction of fires, we lso ttempted to quntify the longevity of fire retention on the tree cnopies. Dt were collected only during the second genertion ecuse hevy rin event (17.8 cm), 1 week fter the first genertion ppliction dislodged 1% of pplied fires. Immeditely fter ppliction, trees were inspected for fires. Fires were found to either completely dhere flt ginst the surfce of tree wood nd leves or to prtilly dhere nd lso prtilly hng off of the sustrte. Twenty-five completely nd 25 prtilly dhering fires were tgged nd monitored weekly per replicte from 13 July to 28 Septemer 24. Attrctiveness of point source dispensers Two experiments were conducted to determine the ttrctiveness of Scentry fires or Hercon flkes to codling moth mles. All tretments were evluted y moth ctch in plstic delt trps descried ove. In the first experiment, conducted from 14 My to 15 July 24, the dispenser tretments compred were: one, eight or 24 fires or flkes. These were compred with trps ited with either one Trécé CM L2 lure or one Suterr CM 1X red septum lure (Suterr, Bend, Oregon) pinned to the upper ceiling of delt trps. Fires nd flkes were plced onto doule-sided sticky tpe nd ffixed to the ceiling of trps. All tretments were deployed in.4-h plots of 2-yer-old Delicious pples 2 3 m tll nd plnted on 3 6 m tree/row spcing t the TNRC. These plots did not receive pplictions of insecticides or pheromone disruption tretments. The experiment ws rrnged in rndomized complete lock with six replictes. Trps were hung pproximtely m ove ground level in the upper third of tree cnopies. Tretments were seprted y t lest 26 m nd rotted weekly. Moths cptured in trps were counted nd removed weekly. In second experiment, conducted from 19 July to 16 Septemer 24, the sme protocol ws followed except tht the 24 flkes nd 24 fires tretments were eliminted. Effect of fire position on disruption of mle moths Studies were conducted to evlute the effects of fire density nd distnce wy from centrlly locted monitoring trp or virgin femle on orienttion of codling moth mles to the trp or femle. Fires were hnd-pplied to pple leves surrounding delt trps or 8 16 cm horizontl pltforms upon which virgin femle ws tethered. In the first experiment, eight fires were deployed in sphere pttern 3, 45 or 6 cm wy from centrl trp or tethered virgin femle. In the second experiment, the distnce from the trp or virgin femle ws mintined constnt t 45 cm nd three densities of fires (four, eight or 16) were compred. For ech experiment, trp or virgin femle without surrounding fires served s control nd the experimentl designs were rndomized complete locks with five replictes. Tretments were deployed in the upper cnopy of trees in plots identicl to those descried for the study Attrctiveness of point source dispensers. Ech tree contined only one tretment nd tretments were seprted y t lest 15 m. Ech tretment ws initilly set up with delt trp ited with.1 mg codlemone lure. The trps were inspected twice weekly y counting nd removing cptured mle moths. Once per week, trps were removed nd tretments were monitored y deploying tethered Journl compiltion 28 The Royl Entomologicl Society, Agriculturl nd Forest Entomology, 1,

4 392 L. L. Stelinski et l. virgin femles. Codling moth pupe were otined from the USDA-ARS Ykim Agriculturl Reserch Lortory in Wpto, Wshington. Pupe were sorted y sex nd dults emerged in 1-L plstic cges contining 5% sucrose in plstic cups with cotton dentl wicks protruding from their lids. Femles (2 3 dys old) were tethered on 8 16 cm plstic pltforms mounted centrlly pproximtely 2.5 m ove ground level within the cnopy of 2 3 m pple trees. Femles were collected from the field pproximtely 18 2 h fter deployments. Dissections were conducted to determine mting sttus y removl of the urs copultrix nd inspection for the presence of spermtophore. In the first genertion (16 My to 8 July 25), tretments were deployed in orchrds otherwise not treted with pheromone. During this first genertion, disruption of mle moth orienttion to trps nd prevention of virgin femle mting ws judged to e poor. We hypothesized tht ckground concentrtion of pheromone, which my e chieved y the lel-rte ppliction of fires, would improve disruption. Thus, in the second genertion (13 July to 1 Septemer 25), ll tretments (including the control) were deployed in orchrds treted with 5 Isomte C-Plus dispensers/h. The Isomte dispensers were plced t lest 6 m from the nerest fire density or distnce loction. A totl of 42 femles were deployed in ech genertion with 29 nd 21 recovered nd dissected during the first nd second genertions, respectively. Anlyses Trpping dt were trnsformed to ln ( x + 1) (to normlize the distriutions nd homogenize vrinces) nd then sujected to nlysis of vrince ( nov ). Fruit injury dt were rcsin trnsformed prior to nov. For the fire deposition study, the numer of fires per ten pnels per loction (etween trees in row, etween rows, or under tree cnopies) ws verged for ech of the four orchrds where the study ws conducted, which were considered s locks for the nov. When nov ws significnt, Tukey s honestly significnt difference test ws used to compre tretment mens (SAS Institute, Cry, North Crolin). Results Smll plot comprison of femle-equivlent dispensers with hnd-pplied reservoir dispensers During the first genertion moth flight, significntly ( F = 9.1, d.f. = 3,9, P =.9) fewer mle codling moths were cptured in monitoring trps in plots treted with ech pheromone tretment compred with the control plots; however, there ws no significnt difference etween the two femle-equivlent dispenser tretments nd Isomte C Plus ( Tle 1 ). In the second genertion, significntly ( F = 6.8, d.f. = 3,9, P =.1) fewer mle codling moths were cptured in plots treted with Scentry fires compred with control plots; however, ctches in plots treted with Hercon flkes nd Isomte C Plus dispensers were not significntly different from the control ( Tle 1 ). Tle 1 Effect of two femle-equivlent dispenser technologies nd Isomte C plus on disruption of mle codling moth orienttion to pheromone trps Tretment Men ± SEM moth cpture/trp First genertion (14 My to 23 July) Second genertion (26 July to 16 Septemer) Control 8.2 ± ± 16.1 Isomte C Plus 4.1 ± ± 5.4, Scentry fires 3.1 ± ± 3.7 Hercon flkes 3.1 ± ± 15.4, Mens within column followed y the sme superscript letter re not significntly different (Tukey s tests, P >.5). Lrge plot comprison of erilly pplied Scentry fires with hnd-pplied Isomte C Plus There ws significnt effect of the locking fctor during the first genertion ( F = 2.5, d.f. = 3,6, P =.1), ut not during the second genertion ( F =.32, d.f. = 3,6, P =.13). During oth the first ( F = 18.3, d.f. = 2,6, P =.8) nd second ( F = 6.3, d.f. = 2,6, P =.5) genertions, significntly fewer mles were cptured in plots treted with Isomte C Plus compred with control plots; however, moth ctch in plots treted with erilly pplied fires ws not different from the control ( Tle 2 ). In the first genertion, moth ctch in Isomte-treted plots ws significntly lower thn in firetreted plots; however, there ws no significnt difference etween these two tretments during the second genertion ( Tle 2 ). Fruit injury t mid-seson ( F = 1., d.f. = 2,6, P =.44) nd t hrvest ( F = 2.1, d.f. = 2,6, P =.19) in the two pheromone tretments nd the control did not differ significntly ( Tle 2 ). Deposition of erilly pplied fires The men ± SE numer of fires lnding etween tree rows (1.71 ±.31) ws significntly ( F = 13.1, d.f. = 2,6, P =.1) greter thn the men numer etween trees within rows (.83 ±.19) or eneth trees (.35 ±.11); however, there ws no difference etween the ltter two loctions. Given tht pproximtely fires were pplied to 441 trees/ h, we clculte tht n estimted fires/h fell to the orchrd floor wheres pproximtely fires/h lnded on trees. Thus, pproximtely 115 fires were deposited per tree. Retention of erilly pplied fires Thirty eight dys fter the eril ppliction of fires, which ws pproximtely mid-wy through the second moth genertion, 68% nd 51% of completely nd prtilly dhering fires, respectively, were found remining on folige ( Fig. 1 ). At 72 dys post-ppliction, pproximtely 38 nd 21% of completely nd prtilly dhering fires, respectively, remined ttched to cnopies ( Fig. 1 ). Journl compiltion 28 The Royl Entomologicl Society, Agriculturl nd Forest Entomology, 1,

5 Femle-equivlent dispensers for disruption of codling moth 393 Tle 2 Effect of erilly pplied Scentry fires nd Isomte C Plus codling moth ctch in pheromone trps nd fruit injury Men ± SEM moth cpture/trp Men ± SEM % fruit injury Tretment First genertion Second genertion Mid-seson Hrvest Control 4.3 ± ± ± ±.43 Isomte C Plus 13.4 ± ± ± ± 3.2 Scentry fires 38.8 ± ± 6.7,.17 ±.9.27 ±.16 Mens within column followed y the sme superscript letter re not significntly different (Tukey s tests, P >.5). Attrctiveness of point source dispensers Delt trps ited with Trécé L2 lures nd Suterr 1X red septum lures cptured significntly ( F = 1.7, d.f. = 7,35, P <.1) more mle codling moth thn ny of the Scentry fire or Hercon flke tretments during the first genertion flight ( Tle 3 ). Trps ited with one, eight nd 24 Scentry fires nd those ited with one or eight Hercon flkes cptured sttisticlly equivlent numers of moths ( Tle 3 ). Significntly fewer mles were cptured in trps ited with 24 Hercon flkes thn in trps ited with one, eight or 24 Scentry fires ( Tle 3 ). During the second genertion, significntly ( F = 15.5, d.f. = 5,25, P =.1) more mles were cptured in trps ited with Trécé L2 nd Suterr 1X red septum lures thn in trps ited with 1 or 8 Hercon flkes; however, there ws no significnt difference etween ctch in trps ited with the two lure types nd those ited with one or eight Scentry fires ( Tle 4 ). Effect of fire position on disruption of mle moths In plots otherwise not treted with pheromone, significntly ( F = 7.4, d.f. = 3,16, P =.1) fewer mle C. pomonell were cp tured in trps ited with.1-mg lures when eight surrounding fires were plced 3, 45, or 6 cm wy from the trp compred with trps not surrounded with fires ( Fig. 2A ). There ws no significnt difference in mle ctch etween the three distnce tretments ( Fig. 2A ). In plots treted with low rte of Isomte C Plus, there ws no significnt ( F =.8, d.f. = 3,16, P =.9) difference etween moth ctch in control trps nd those surrounded y fires t the three distnces tested ( Fig. 2A ). In untreted plots, significntly ( F = 17.3, d.f. = 3,16, P =.1) fewer mle moths were cptured with four, eight nd 16 surrounding fires plced 45 cm wy from centrl trp compred with control trps without surrounding fires ( Fig. 2B ). However, in plots treted with ckground tretment of Isomte C Plus, there ws no significnt ( F = 1.1, d.f. = 3,16, P =.3) difference in moth ctch etween untreted trps nd those surrounded y four, eight or 16 fires plced 45 cm wy from trps ( Fig. 2A ). In otherwise untreted plots, mting ws significntly ( F = 6.2, d.f. = 3,16, P =.4) reduced when eight fires were deployed 3 nd 45 cm wy from tethered virgin femles compred with controls; however, mting ws not significntly reduced compred with the control when fires were plced 6 cm wy from femles ( Fig. 3A ). In plots treted with low density of Isomte C Plus, mting ws significntly ( F = 8.8, d.f. = 3,16, P =.3) reduced only when fires were 3 cm wy from femles ( Fig. 3A ). In oth untreted plots ( F = 7.1, d.f. = 3,16, P =.4) nd plots treted with ckground of pheromone ( F = 1.4, d.f. = 3,16, P =.1), mting ws significntly reduced compred with the control when eight nd 16 fires were plced 45 cm wy from centrl tethered virgin femles; however, four fires 45 cm wy from femles did not significntly reduce mting compred with control femles ( Fig. 3B ). Percentge of mrked fires remining Completely dhering on dy Prtilly dhering on dy. 7/12 7/26 8/9 8/23 9/6 9/2 Dys post tretment Figure 1 Percentge of fires remining on tree wood nd folige t vrious intervls fter eril ppliction of 16 g of fires/h (pproximtely fires/h). Tle 3 Cumulted cptures of mle codling moth in trps ited with vrious dispensers or lures during the first genertion moth flight (14 My to 15 July) Dispenser or lure type Men ± SEM moth cpture/trp Trécé L2 lure 76.3 ± 11.5 Suterr 1X Red Septum 53.8 ± 1.5 One Scentry fire 24.8 ± 4.6 Eight Scentry fires 3.3 ± Scentry fires 26. ± 4.6 One Hercon flke 19. ± 6.4,c Eight Hercon flkes 16. ± 5.3,c 24 Hercon flkes 11.2 ± 3.6 c Mens followed y the sme superscript letter re not significntly different (Tukey s tests, P >.5). Journl compiltion 28 The Royl Entomologicl Society, Agriculturl nd Forest Entomology, 1,

6 394 L. L. Stelinski et l. Tle 4 Cumulted cptures of mle codling moth in trps ited with vrious dispensers or lures during the second genertion moth flight (19 July to 26 August) Dispenser or lure type Trécé L2 lure Suterr 1X Red Septum One Scentry fire Eight Scentry fires One Hercon flke Eight Hercon flke Discussion Men ± SEM moth cpture/trp 11.8 ± ± ± 21.4, 34. ± 13.3, 27.3 ± ± 14.5 Mens followed y the sme letter re not significntly different (Tukey s tests, P >.5). The present study demonstrted tht the efficcy of femleequivlent dispensers cn e equivlent to tht of polyethylene - tue reservoir tues in disrupting codling moth. However, prcticl drwcks of eril ppliction nd poor retention of the pplied formultion limit the effectiveness of Scentry fires. When pplied to tree folige y hnd to mximize the potentil of retention, Hercon flkes were not s effective in disrupting codling moth orienttion to trps s were Scentry fires, which were equivlent to Isomte dispensers in efficcy. This my e explined y the slightly greter ttrctiveness of Scentry fires thn Hercon flkes s determined y the trpping study ( Tles 3 nd 4 ). In ddition, clusters of eight nd 24 Scentry fires nd eight nd 24 Hercon flkes were s ttrctive s individul dispensers of ech type, indicting tht clusters of multiple dispensers should lso function s ttrctive point sources when deployed from mechnized spry equipment. When pplied erilly to 4-h locks of commercil pple, Scentry fires were s effective s hnd-pplied Isomte dispensers in disrupting mle orienttion to trps during the second genertion of moth flight. Fruit injury ws lso equivlent etween plots treted with Scentry fires nd Isomte dispensers; however, this result ws proly ffected y concurrent pplictions of insecticides under commercil growing stndrds. The lck of effective disruption during the first genertion ws due to hevy rin event 1 week fter ppliction, which dislodged 1% of the pplied formultion. During the second genertion, 7% of pplied fires remined on tree folige 5 weeks fter ppliction nd hlf of the fires were still present on the seventh week. This corresponds to pproximtely 5 fires/tree fter 7 weeks sed on n 1 A No pheromone 1 Bckground pheromone 8 8 Men numer of mles per trp ± SEM Control 3 cm 45 cm 6 cm Control 3 cm 45 cm 6 cm Fire distnce wy from trp B No pheromone 1 Bckground pheromone Control 4 fires 8 fires 16 fires Control 4 fires 8 fires 16 fires Fire density surrounding trp Figure 2 Men numer ± SE of mle codling moths cptured in pheromone trps ited with.1-mg lures surrounded y (A) 8 fires plced 3, 45, or 6 cm wy from the trp or (B) four, eight or 16 fires plced 45 cm wy from the trp in plots not treted with pheromone or treted with 5 Isomte C plus dispensers per hectre. Mens followed y the sme letter re not significntly different (Tukey s tests, P >.5). Journl compiltion 28 The Royl Entomologicl Society, Agriculturl nd Forest Entomology, 1,

7 Femle-equivlent dispensers for disruption of codling moth A No pheromone.6 Bckground pheromone.4.4 Proportion of femle mted ± SEM B.2 Control 3 cm 45 cm 6 cm Control 3 cm 45 cm 6 cm Fire distnce wy from femle.6 No pheromone Bckground pheromone Control 4 fires 8 fires 16 fires Control 4 fires 8 fires 16 fires Fire density surrounding femle Figure 3 Men proportion ± SE of tethered virgin femle codling moths tht were mted fter one night in the field when surrounded y (A) eight fires plced 3, 45, or 6 cm wy from the femle or (B) four, eight or 16 fires plced 45 cm wy from the femle in plots not treted with pheromone or treted with 5 Isomte C plus dispensers per hectre. Mens followed y the sme letter re not significntly different (Tukey s tests, P >.5). estimted 115 fires relized per tree on the dy of ppliction. The eril ppliction of fires ws highly inefficient with lmost 44% of the formultion flling to the orchrd floor where it does not contriute to disruption. Recently, trctor-mounted mechnicl pplictor ws developed for Scentry fires similr to the one descried y Stelinski et l. (26), which my improve efficiency of fire deposition onto trees. However, even with 5 fires/tree, only 62 76% nd 7% disruption were otined in the smll nd lrge plot experiments, respectively, suggesting tht this density of fires per re of crop ws not sufficient for effective disruption under the codling moth popultion densities oserved in these studies. Another drwck of this technology, in ddition to low efficiency of product dherence to crop folige, ws poor rinfstness. Hevy rins rendered the first genertion ppliction completely ineffective nd the formultion ws lso progressively lost over the course of the second genertion ( Fig. 1 ). Incresing the effectiveness of the Bio-Tk sticker dhesive is potentil solution; however, highly effective sticker during second genertion ppliction when pples re present my e uncceptle if fires remin on hrvested fruit. This my e prticulrly difficult prolem to overcome for fire formultion trgeting codling moth, given the phytotoxicity of the codlemone ctive ingredient ( Giroux & Miller, 21 ). Mle codling moths were cptured in monitoring trps nd mted with tethered virgin femles tht were surrounded y eight fires 3 cm wy or 16 fires 45 cm wy. Although disruption ws improved y incresing the numer of fires surrounding monitoring trp or tethered virgin femle, s well s y decresing the distnce etween the fires nd trps or femles, relized disruption ws never ove 82%. Mle orientl fruit moths, Grpholit molest (Busck), re cple of efficiently discriminting etween multiple overlpping pheromone plumes ( Vleur & Löfstedt, 1996 ). Moreover moths re known to efficiently discriminte the oundries of pheromone plumes within homogenous ckground concentrtions of pheromone ( Snders, 1996; Schofield et l., 23 ). The current results otined with the codling moth re consistent with these previous findings nd imply tht ferl mle codling moth were cple of discriminting mong multiple plumes (i.e. those emnting from the trp or femle s well s those from surrounding fires). It ppers tht persistent serching ehvior exhiited y portion (pproximtely 13%) of those moths hving oriented to trps or femles surrounded y fires resulted in successful loction of the centrl trp or femle. In oth otherwise untreted nd Isomte-treted plots, 4 39% of femles surrounded with four to 16 fires were mted. Therefore, clling femles perched t lest 3 cm wy from fires re Journl compiltion 28 The Royl Entomologicl Society, Agriculturl nd Forest Entomology, 1,

8 396 L. L. Stelinski et l. vulnerle of eing mted. It is possile tht the femle s nturl multi-component pheromone ( Witzgll et l., 21 ) is more ttrctive to mles thn the synthetic codlemone lone relesed from fires. Effective disruption of codling moth ppers to e dependent on oth competitive ttrction of mles to plumes of synthetic pheromone nd susequent centrl nervous system hitution of mle response due to overexposure ( Witzgll et l., 28 ). Isomte C Plus dispensers re known to oth ttrct mle codling moths ( Brrett, 1995; Knight et l., 1999; Stelinski et l., 24, 25 ) nd rief exposure within metres of such dispensers strongly hitutes the mles centrl nervous system ( Stelinski et l., 26 ). Given their relese rte of pproximtely.1 g/h ( Wetherston et l., 1985 ), fires proly disrupt mle orienttion y competitive ttrction without ssocited hitution ( Stelinski et l., 26 ) nd, thus, the efficcy of this formultion will e highly dependent on codling moth density. Future improvements to femle-equivlent technologies tht my improve efficcy include: (i) improving mechnicl ppliction so greter proportion of pplied formultion dheres to tree cnopies; (ii) incresing ttrctiveness of individul dispensers; nd (iii) incresing relese rte per dispenser (which my require decresing point source density per re of crop) to increse the likelihood of sensory hitution. Acknowledgements This reserch ws supported y grnt from the Wshington Stte Tree Fruit Commission. A previous version of the mnuscript ws improved y W. Meyer, F. M. de Lme, G. Krwczyk, J. Wlgench nd L. Teixeir. We re lso grteful to five nonymous reviewers who improved previous version of the mnuscript. References Angeli, G., Anfor, G., Bldessri, M., Germinr, G.S. Rm, F., De Cristofro, A. & Ioritti, C. ( 27 ) Mting disruption of codling moth Cydi pomonell with high densities of Ecodin sex pheromone dispensers. Journl of Applied Entomology, 131, Brrett, B. ( 1995 ) Effect of synthetic pheromone permetion on cptures of mle codling moth (Lepidopter: Tortricide) in pheromone nd virgin femle moth-ited trps t different tree heights in smll orchrd locks. Environmentl Entomology, 24, Brunner, J., Welter, S., Clkins, C. et l. ( 22 ) Mting disruption of codling moth: perspective from the Western United Sttes. IOBC WPRS Bulletin, 25, Crdé, R.T. & Minks, A.K. ( 1995 ) Control of moth pests y mting disruption: successes nd constrints. Annul Review of Entomology, 4, Crdé, R.T., Bker, T.C. & Cstrovillo, P.J. ( 1977 ) Disruption of sexul communiction in Lspeyresi pomonell (codling moth), Grpholith molest (Orientl fruit moth) nd G. prunivor (lesser ppleworm) with hollow fier ttrctnt sources. Entomologi Experimentlis et Applict, 22, Epstein, D., Gut, L., McGhee, P. & Hs, M. ( 23 ) Evlution of new mting disruption formultions. Proceedings of the 77th Annul Western Orchrd Pest nd Disese Mngement Conference, Portlnd, Oregon, Jnury, pp Wshington Stte University, Pullmn, Wshington. Epstein, D.L., Stelinski, L.L., Reed, T.P., Miller, J.R. & Gut, L.J. ( 26 ) Higher densities of distriuted pheromone sources provide disruption of codling moth (Lepidopter: Tortricide) superior to tht of lower densities of clumped sources. Journl of Economic Entomology, 99, Giroux, P.Y. & Miller, J.R. ( 21 ) Phytotoxicity of pheromonl chemicls to fruit tree folige: chemicl nd physiologicl chrcteriztion. Journl of Economic Entomology, 94, Knight, A.L. ( 24 ) Mnging codling moth (Lepidopter: Tortricide) with n internl grid of either erosol Puffers or dispenser clusters plus order pplictions of individul dispensers. Journl of the Entomologicl Society of British Columi, 11, Knight, A.L. & Lrsen, T.E. ( 24 ) Improved deposition nd performnce of microencpsulted sex pheromone formultion for codling moth (Lepidopter: tortricide) with low volume ppliction. Journl of the Entomologicl Society of British Columi, 11, Knight, A.L., Croft, B.A. & Bloem, K.A. ( 1999 ) Effect of mting disruption dispenser plcement on trp performnce for monitoring codling moth (Lepidopter: Tortricide). Journl of the Entomologicl Society of British Columi, 96, Snders, C.J. ( 1996 ) Mechnisms of mting disruption in moths. Insect Pheromone Reserch: New Directions ( ed. y R. T. Crdé nd A. K. Minks ), pp Chpmn nd Hll, New York, New York. Schofield, S.W., Justus, K.A., Mfr-Neto, A. & Crdé, R.T. ( 23 ) Flight of mle Cdr cutell long plumes of ir nd pheromone superimposed on ckgrounds of pheromone. Entomologi Experimentlis et Applict, 19, Shorey, H.H. & Gerer, R.G. ( 1996 ) Use of puffers for disruption of sex pheromone communiction of codling moths (Lepidopter: Tortricide) in wlnut orchrds. Environmentl Entomology, 25, Stelinski, L.L., Gut, L.J., Pierzchl, A.V. & Miller, J.R. ( 24 ) Field oservtions quntifying ttrction of four tortricid moth species to high-dosge, polyethylene-tue pheromone dispensers in untreted nd pheromone-treted orchrds. Entomologi Experimentlis et Applict, 113, Stelinski, L.L., Gut, L.J., Epstein, D. & Miller, J.R. ( 25 ). Attrction of four tortricid moth species to high dosge pheromone rope dispensers: oservtions implicting flse plume following s n importnt fctor in mting disruption. IOBC/WPRS Bulletin, 28, Stelinski, L.L., Gut, L.J. & Miller, J.R. ( 26 ) Orienttionl ehviors nd EAG responses of mle codling moth fter exposure to synthetic sex pheromone from vrious dispensers. Journl of Chemicl Ecology, 32, Stelinski, L.L., Miller, J.R. Ledeuhr, R. & Gut, L.J. ( 26 ) Mechnized pplictor for lrge-scle field deployment of prffin-wx dispensers of pheromone for mting disruption in tree fruit. Journl of Economic Entomology, 99, Stelinski, L.L., Gut, L.J., Hs, M., McGhee, P. & Epstein, D. ( 27 ) Evlution of erosol devices for simultneous disruption of sex pheromone communiction in Cydi pomonell nd Grpholit molest (Lepidopter: Tortricide). Journl of Pest Science, 8, Swenson, D.W. & Wetherston, I. ( 1989 ) Hollow-fier controlledrelese systems. Insect Pheromones in Plnt Protection ( e d. y A. R. Jutsum nd R. F. S. Gordon ), pp Whiley, U.K. Journl compiltion 28 The Royl Entomologicl Society, Agriculturl nd Forest Entomology, 1,

9 Femle-equivlent dispensers for disruption of codling moth 397 Thomson, D.R., Gut, L.J. & Jenkins, J.W. ( 1999 ) Pheromones for insect control: strgegies nd successes. Biopesticides: Use nd Delivery ( ed. y F. R. Hll nd J. J. Menn ), pp Humn Press, Totow, New Jersey. Vleur, P.G. & Löfstedt, C. (1996 ) Behvior of mle orientl fruit moth, Grpholit molests, in overlpping sex pheromone plumes in wind tunnel. Entomologi Experimentlis et Applict, 79, Wldner, W. ( 1997 ) Three yers of lrge-scle control of codling moth y mting disruption in the South Tyrol, Itly. IOBC WPRS Bulletin, 2, Wetherston, I., Miller, D. & Lvoic-Dornik, J. ( 1985 ) Cpillries s controlled relese devices for insect pheromones nd other voltile sustnces reevlution: prt II. Predicting relese rtes from Celcon nd Teflon cpillries. Journl of Chemicl Ecology, 11, Witzgll, P., Bengtsson, M., Ruscher, S. et l. ( 21 ) Identifiction of further sex pheromone synergists in the codling moth, Cydi pomonell. Entomologi Experimentlis et Applict, 11, Witzgll, P., Stelinski, L., Gut, L. & Thomson, D. ( 28 ) Codling moth mngement nd chemicl ecology. Annul Review of Entomology, 53, Accepted 23 Mrch 28 First pulished online 17 Septemer 28 Journl compiltion 28 The Royl Entomologicl Society, Agriculturl nd Forest Entomology, 1,