H E Development and Evaluation of an Emulsiﬁed Parafﬁn …The release proÞles of three experimental emulsi-Þed wax formulations and Confuse-OFM were deter-mined in the laboratory

HORTICULTURAL ENTOMOLOGY

Development and Evaluation of an Emulsified Paraffin Wax Dispenserfor Season-Long Mating Disruption of Grapholita molesta

in Commercial Peach Orchards

FREDERIQUE M. DE LAME,1,2 JAMES R. MILLER,1 CYNTHIA A. ATTERHOLT,3

AND LARRY J. GUT1

J. Econ. Entomol. 100(4): 1316Ð1327 (2007)

ABSTRACT The University of California at Davis patented the use of emulsiÞed wax to releasepheromones for mating disruption. Advantages of these dispensers include low cost, self-adhesion, andbiodegradation. We compared the efÞcacy and practicality of Confuse-OFM, a commercial emulsiÞedwax formulation of oriental fruit moth,Grapholita molesta (Busck), pheromone with those of Check-Mate OFM-F sprayable pheromone and Isomate-M 100 polyethylene tube dispensers in commercialpeach (Prunus spp.) orchards. EfÞcacy was measured with male captures in pheromone-, virginfemale-, and liquid attractant-baited bucket traps as well as by noting injury to shoots and fruit. Twoapplications of Confuse-OFM were as effective as two applications of CheckMate OFM-F and oneapplication of Isomate-M 100. However, Confuse-OFM was tedious to apply and wasted pheromonewith an initially high release rate. We developed a new emulsiÞed wax formulation (Wax Dollops)that maintained release rates above a 5 mg/ha/h threshold twice as long as Confuse-OFM in thelaboratory. Field trials conÞrmed that one application of 3-ml dollops (590 dollops per ha) providedseason-long (�15 wk) control equivalent to that of Isomate-M 100 and Confuse-OFM applied asdescribed above. Several applicators were developed for Wax Dollops, including a pneumatic gun thatshot dollops �2 m. However, the most efÞcient method for application was wiping dollops onto treebranches by using a ßat-bladed spatula. This research was the basis for a new line of commercialpheromone pest control products equally effective to current commercial formulations but withadvantages in cost and ßexibility.

KEY WORDS Grapholita molesta, mating disruption, pheromone dispenser, emulsiÞed wax

The availability of a controlled release device to dis-pense pheromone for an extended period can be alimiting factor in the adoption of mating disruptionprograms by growers (Plimmer and Inscoe 1978, Sid-dall 1978, Rothschild 1979, Jackson 1989, Weatherston1990). Although it is unlikely that any one dispenserwould meet all of the following criteria, an ideal hand-applied dispenser should steadily release just enoughpheromone to preclude mating of the target insect fora full season, be inexpensive to manufacture and easyto apply, and be environmentally friendly (Plimmer1981). Isomate-M 100 and M Rosso polyethylene tubedispensers (Shin-Etsu Chemical Co., Ltd., Tokyo, Ja-pan) are currently the most widely used hand-appliedpheromone dispensers for mating disruption of theoriental fruit moth,Grapholita molesta (Busck) (Lep-idoptera: Tortricidae) (Rice and Kirsch 1990, Pree et

al. 1994, Trimble et al. 2004). Although they releasepheromone steadily for prolonged periods, due to theappreciable costs of purchase and labor for hand ap-plication, polyethylene tube dispensers are not widelyadopted in some production systems.

Atterholt (1996) and colleagues (Atterholt et al.1998, Delwiche et al. 1998) developed a biodegrad-able, parafÞn-based emulsiÞed wax dispenser that, af-ter application as a liquid, released pheromone at asteady rate for over 130 d under controlled laboratoryconditions. In a 4-mo-long Þeld trial in peaches(Prunus spp.), this emulsion controlled G. molesta aseffectively as Hercon (Hercon Environmental, Emigs-ville, PA) and Consep (Consep, Inc., now SuterraLLC, Bend, OR) hand-applied pheromone dispensers,as measured by inhibition of male moth captures inpheromone traps and shoot damage (Atterholt 1996).After patenting by the University of California at Davis(U.S. Patent 6,001,346, Delwiche et al. 1999), severalcompanies attempted to commercialize this emulsion.From 2000 to 2002, Gowan Co. (Yuma, AZ) exploredmarketing an emulsiÞed wax formulation ofG.molestapheromone (Confuse-OFM). Confuse-OFM was lessviscous than the formulation of Atterholt (1996); it

1 Department of Entomology, Michigan State University, 243 Nat-ural Science Bldg., East Lansing, MI 48824.

2 Current address: Henkel Consumer Goods Inc., Dial Center forInnovation, 15101 N. Scottsdale Rd., Scottsdale, AZ 85254 (e-mail:[email protected]).

3 Department of Chemistry and Physics, Western Carolina Univer-sity, 231 Natural Sciences Bldg., Cullowhee, NC 28723.

0022-0493/07/1316Ð1327$04.00/0 � 2007 Entomological Society of America

resembled white, liquid glue, and it was applied usingsquirting devices such as forestry paint marking gunsand plastic squirt bottles.

This article reports on 1) the efÞcacy of Confuse-OFM, as supplied by Gowan Co., versus the efÞcaciesof two other commercialG.molestamating disruptionformulations; 2) the development of an improvedemulsiÞed parafÞn wax formulation (Wax Dollops)with enhanced longevity compared with Confuse-OFM and suitable for the cold Michigan climate; 3)the efÞcacy of Wax Dollops compared with the efÞ-cacies of Confuse-OFM and Isomate-M 100; 4) therelease proÞles of Confuse-OFM and Wax Dollops inthe laboratory and Þeld; and 5) the development of acheap and effective applicator for Wax Dollops.

Materials and Methods

2001 Field Tests

Efficacy of Confuse-OFM. The efÞcacy of Confuse-OFM (Gowan Co.) was directly compared with thoseof Isomate-M 100 polyethylene tubes (Shin-EtsuChemical Co., Ltd., Tokyo, Japan), CheckMateOFM-F microencapsulated sprayable formulation(Suterra LLC), and a no-pheromone treatment. Con-fuse-OFM was applied using a 1-liter plastic squirtbottle at the recommended rate of 74 g active ingre-dient (AI) or 580 deposits per hectare per G. molestageneration. Each deposit consisted of �2.7 ml (2.6 g)of Confuse-OFM and was applied to the top surfacesof tree branches at a height of 1.5Ð1.8 m. Isomate-M100 was hand applied once at the beginning of theseason at the recommended rate of 57 g AI (250 dis-pensers) per hectare at the same height as Confuse-OFM. CheckMate OFM-F was applied at 74 g AI/haper G. molesta generation with an air-blast sprayer.The active ingredient in all formulations was a 93:6:1blend of (Z)-8-dodecenyl acetate [(Z)8-12:Ac]:(E)-8-dodecenyl acetate [(E)8-12:Ac]:(Z)-8-dodecanol[(Z)8-12:OH].

The trials were carried out in mature commercialpeach orchards in Berrien Springs and Coloma, MI.Treatments were replicated on four farms and blockedby farm. Treated plots ranged from 0.8 to 3.6 ha, andmost plots were planted with peach varieties har-vested in early to mid-August, coinciding with thebeginning of the third ßight ofG.molesta in Michigan.The peach trees in all plots were �3 m in height.Insecticide sprays were not eliminated from phero-mone-treated plots, but the number of sprays specif-ically targeting G. molesta was reduced in most plots.

Each orchard was monitored for activity of maleG.molestawith three to Þve delta-style Scenturion pher-omone traps baited with Scenturion septa-based G.molesta lures (Suterra LLC). Confuse-OFM and no-pheromone plots also were monitored with Þve at-tractant-baited bucket traps during the second G.molesta generation. These green, yellow, and whitebucket traps (Great Lakes IPM, Vestaburg, MI) con-tained �500 ml of a liquid bait composed of 10 ml ofterpinyl acetate (Aldrich Chemical Co., Milwaukee,

WI), 1 ml of Tween 20 emulsiÞer (Aldrich ChemicalCo.), 1.8 kg of brown sugar, and 18.9 liters of water(Atanassov et al. 2002). Pheromone traps were mon-itored biweekly. At each sampling date, male mothscaught in the traps were counted and removed. Lureswere replaced once perG. molesta generation (�6Ð8wk). Sticky liners were replaced when soiled or atleast once per G. molesta generation. Bucket trapswere monitored once per week. Each bucket trap wasemptied, rinsed with water, and reÞlled with fresh baitat each sampling date. All traps were hung at 1.5Ð1.8m in the outer one third of tree canopies.G.molesta injury to shoots was evaluated at the ends

of the Þrst and second generations. Three hundredand sixty to 400 shoots were examined in the plotinteriors (deÞned as trees not located in the outer tworows or the outer three trees within rows) for evi-dence of feeding byG.molesta larvae in the tips (shootßagging). Ten randomly chosen shoots in the top halfand 10 randomly chosen shoots in the bottom half ofrandomly chosen, nonadjacent trees in nonadjacentrows were examined for shoot ßagging. Flagged shootswere dissected to reveal G. molesta larvae.

Larval fruit injury was evaluated just before harvestby examining 540Ð600 fruit in the interior of each plot.Although it is desirable to cut open all fruit evaluatedfor internal worm injury (Trimble et al. 2001), a smallpeach crop in Michigan in 2001 and 2002, combinedwith the high market value of available fruit, limitedthe number that could be removed from these com-mercial orchards. Thus, fruit injury evaluations en-tailed careful examination of the fruit without remov-ing them from trees. Fruit with any external evidenceof insect feeding were picked and cut to conÞrmtunneling or the presence of a G. molesta larva.Pheromone Field Release Profile of Confuse-OFM.

The pheromone release proÞle of Confuse-OFM wasdetermined in an apple (Malus spp.) orchard at theTrevor Nichols Research Complex, Fennville, MI. Ap-proximately 2.7 ml of Confuse-OFM was applied as an�12.5-cm by 1-cm by 2-mm (length by width bydepth) deposit to individual hardwood tongue depres-sors (15.2 by 1.9 cm) by using a 1-liter plastic squirtbottle. Treated tongue depressors were air-dried on ahorizontal surface for �12 h. The treated depressorswere then afÞxed vertically at 30.5-cm intervals to3-m-long plastic ropes. The ropes had been hung hor-izontally �1.8 m from the ground in the outer onethird of the north sides of the canopies of Þve 3.8-m-tall apple trees. All wax deposits faced east. Experi-ments were initiated in early June. Five depressorstreated with Confuse-OFM were randomly selectedfor collection at time zero. Subsequently, Þve treateddepressors, one randomly selected from each tree,were collected at weekly intervals over 11 wk. Imme-diately after collection, the treated depressors wereindividually placed in 500-ml clear-glass, wide-mouthed French square bottles with tinfoil-linedblack plastic caps (Qorpak, Bridgeville, PA) and keptat �10 to �20�C until analysis.

Pheromone was extracted from the dispensers byusing a method modiÞed from Meissner et al. (2000).

August 2007 DE LAME ET AL.: WAX DISPENSER FOR MATING DISRUPTION 1317

The bottles containing the dispensers were removedfrom the freezer and brought to room temperature.Four hundred milliliters of acetonitrile (HPLC grade,EM Science, Merck KGaA, Darmstadt, Germany) wasadded to each bottle, followed by 62.6 mg of tride-canoic acid methyl ester (98%, Sigma-Aldrich, St.Louis, MO) in 1 ml of acetonitrile as the internalstandard. The bottles were placed in a rotary-shakerwater bath (Orbit Shaker Bath model 3540, Lab LineInstruments, Inc., Melrose Park, IL) set between 70and 75�C for 10 min; thereafter, they were shaken at150 rpm for 30 s. The bottles were then left in the waterbath for another 3 min, followed by shaking for an-other 30 s. They were then stored at �20�C for at least24 h, during which time the wax solidiÞed and settledto the bottom of the jar. Upon retrieval from thefreezer, 1 ml of the solvent was removed from each jar.Each sample was Þltered through a disposable glasspipette containing an �5.5- by 5.5-cm piece of Kim-wipe (Kimberly-Clark Corp., Roswell, GA) stuffed toform a plug at the tapered end of the pipette into a1.5-ml gas chromatography (GC) vial (Supelco, Belle-fonte, PA). Pheromone in the sample was quantiÞedusing a Series 6890 Agilent GC (Agilent Technologies,Palo Alto, CA) equipped with a 30-m HP DBWAXETRpolar column (Hewlett Packard, Palo Alto, CA). He-lium carrier gas ßowed through the column at a con-stant 20 psi. The oven was held at 130�C for 2 min, andthen it was ramped to 160�C (2.5�C/min) and to 250�C(40�C/min). Pheromone was quantiÞed using the in-ternal standard method (McNair and Miller 1998).

Developing Wax Dollops

The release proÞles of three experimental emulsi-Þed wax formulations and Confuse-OFM were deter-mined in the laboratory. The experimental formula-tions were prepared per Atterholt (1996), but withcompositions modiÞed to yield wax emulsions of in-creasing viscosity. Emulsion C was most viscous, fol-lowed by emulsion B, and then emulsion A. EmulsionA was thicker than Confuse-OFM. The experimentalformulations all contained 5% G. molesta pheromone[93:6:1 blend of (Z)8-12:Ac:(E)8-12:Ac:(Z)8-12:OH,Shin-Etsu Chemical Co., Ltd.].

The release proÞles of the four formulations weredetermined by quantifying pheromone remaining inthe respective wax deposits after aging in laboratoryfume hoods. Three milliliters of each formulation wasapplied to3.8-by35-cmstripsofheavy-dutyaluminumfoil. Two pennies were taped to the bottom of eachstrip to keep them from swaying in the air ßowingthrough the hoods. The experimental wax formula-tions were applied as �2.5-cm-diameter, 0.3-cm-thickdollops in the centers of the aluminum foil strips byusing a 20-ml syringe with a cutoff tip (2-cm-diameteropening). This application method gave the dispens-ers a shape very similar to that realized in the Þeldwhen applied with the pneumatic gun applicator (de-scribed below). Confuse-OFM was applied 3 cm fromthe top of the foil strip. Foil strips on which Confuse-OFM was applied were immediately placed in a ver-

tical position to allow the deposit to run down thestrip, as it was observed to do when applied to treelimbs in the Þeld. In no case did material drip from thefoils before hardening. After application to the foilstrips, the formulations were left to dry on a horizontalsurface under ambient conditions for �12 h beforebeing hung vertically in the fume hoods.

Five strings were stretched tightly across each oftwo 1.5-m-wide fume hoods, �1 m above the worksurfaces inside the hoods. Four foil strips of eachtreatment were randomly chosen for collection attime zero. The remaining treated strips were hung sideby side along the lengths of the strings (40 foil stripsper string) and secured to these using small paperclips. Fourteen collections were made over 24 wk. Oneach collection date, two randomly selected strips ofeach treatment were collected from each hood (fourstrips total). Temperatures in the hoods were re-corded weekly, and they remained between 22 and24�C for the duration of the experiment. The collec-tion and analysis protocols were identical to thosedescribed above for the determination of the phero-mone release proÞle of Confuse-OFM in the Þeld.

2002 Field Tests

Efficacy ofWax Dollops. Emulsion C1 (emulsion Cwith minor alterations in ingredient proportions) wasselected for Þeld testing. Pilot applications of 3-mldollops to tree branches before the Þrst ßight of G.molesta revealed that freezing and thawing resulted insome dislodgement of dollops from tree bark. This hadnot been a problem with Confuse-OFM. We postulatethat this issue arose due to the relatively low surfacearea-to-volume ratio of emulsion C1, which resulted ina smaller surface of attachment for a similar weight ofwax for this formulation versus Confuse-OFM. To re-solve this problem, emulsions C2 and C3, incorporat-ing adhesive, were developed. Addition of the adhe-sive did not inßuence pheromone release rates fromthe dispensers (see below).

Except for the differences noted below, the 2002Þeld trials were carried out identically to the 2001 Þeldtrials. The experiment was replicated on four com-mercial peach farms in Coloma. The peach plots weremade up of trees of similar size, and fruit was harvestedat similar times as those in the 2001 trial plots. As in2001, insecticide treatments were not eliminated fromthe pheromone-treated plots, but they were reducedin most of these plots.

The formulations tested were Confuse-OFM, Iso-mate-M 100, and Wax Dollops (mixed treatments ofemulsions C2 and C3). Their efÞcacies were com-pared with that of a no-pheromone treatment. TheConfuse-OFM treatment differed from that in the2001 test; it was applied as 3-ml (2.8 g) deposits withforestry paint-marking guns (essentially, heavy dutysquirt bottles) (Idico Products Co., New York, NY) for520 deposits per ha in total. Wax Dollops were appliedat 74 g AI (590 dollops) per ha as 3-ml (2.5-g) dollopsby using a swipe applicator (described below). Thedollops initially applied on 19 April were emulsion C2

1318 JOURNAL OF ECONOMIC ENTOMOLOGY Vol. 100, no. 4

and contained a low level of adhesive, which provedto be insufÞcient in some cases. Some dollops werereplaced with emulsion C3 (with a higher level ofadhesive) as late as 6 wk after the initial application.SpeciÞcally, �12 and 15% of dollops, respectively,were replaced on farms 1 and 2 at the end of May. Theoriginal dollops deployed on farms 4 and 5 were ap-plied as the sun was setting (until �2130 hours) on 19April. Thus, those treatments had little chance to drybefore experiencing freezing nighttime temperaturesand when the plots were surveyed on 3 May, �33% ofdollopshad fallen fromthe trees.Therefore, all dollopson farm4and�50%ofdollopson farm5were replacedwith emulsion C3 between early and mid-May.

Four pheromone traps and four bucket traps wereplaced in each plot before the Þrst ßight ofG.molesta.Additionally, male G. molesta activity was monitoredin all plots by using virgin female traps. Virgin femalesoriginated from a colony collected as larvae in aninfested apple orchard in Fennville, MI, in July 2001.This colony was reared on a pinto bean-based diet(Shorey and Hale 1965) at 24�C and a photoperiod of16:8 (L:D) h. Pupae were sexed (George 1965), andfemales were held individually, under natural lightconditions, in 118-ml plastic cups containing a 2-cm-long cotton wick soaked in 5% sucrose water solution.Two females (�3 d old) were placed in a wire screencage also containing a 2-cm-long cotton wick soakedin 5% sucrose water solution. The screen cage washung in a delta trap (Scenturion, Inc., Clinton, WA).Three to four times during the peak ßight period of theÞrst and second G. molesta generations, Þve virginfemale traps were placed in random locations in theinterior of each plot and at least 8 m from any othertrap. The traps were monitored after 3 d for virginfemale mortality and counts of captured males. Datagathered from traps in which one or more femaleswere absent or dead were not used in the analyses(�20% of traps in each generation). Data were col-lected from 6 to 13 and 10Ð14 traps in each plot ingenerations 1 and 2, respectively.

To estimate levels of G. molesta injury, 400 shootswere examined for larval damage in the interior of allplots. Levels of internal fruit injury in each plot wereevaluated by examining 600 fruit in plot interiors.Pheromone Field Release Profile of Dollops withand without Adhesive. Pheromone Þeld release pro-Þles were determined for emulsion C1 (no adhesive),C2 (low level of adhesive), and C3 (high level ofadhesive). The experiment was initiated in early Juneat the Trevor Nichols Research Complex in Fennville.Three-milliliter dollops of each formulation were ap-plied onto 10.2- by 2.9- by 0.3-cm pieces of wood byusing the procedure used to apply the experimentalformulations to the aluminum strips (see DevelopingWax Dollops). The dollops were left to dry on a hor-izontal surface, at room temperature, for �24 h. A1.8-m by 3.7-cm by 1.8-cm piece of wood was screwedonto branches in the north side of each of Þve 3.8-m-tall apple trees at a height of �1.5Ð1.8 m in the outerone third of the canopy. The smaller, dollop-treatedpieces of wood were screwed horizontally, 1.2 cm

apart, onto the larger pieces of wood with the waxmaterial facing upwards. Five dollops from each treat-ment were randomly selected for collection at timezero. Subsequently, one randomly selected dollop ofeach treatment was collected from each tree (Þvedollops per treatment total) weekly for 8 wk and thenbiweekly for another 8 wk.

The collection and analysis protocols were identicalto those described for determining the pheromoneÞeld release proÞle of Confuse-OFM (see above),except thatonly200mlof acetonitrilewasadded to thesample bottles before pheromone extraction. AfterÞltering the extraction solvent, 0.5 ml of that solventwas diluted by half with acetonitrile before phero-mone quantiÞcation. Preliminary GC analyses dem-onstrated that results obtained by using this modiÞedprocedure matched those obtained using the originalprocedure.

Efficiency of Dollop Applicators

Three applicators were developed to dispense WaxDollops. The pneumatic gun applicator consisted of a6.4-cm-long stainless steel barrel Þtted with a 1.3-cm-diameter aluminum piston in front of which 3 ml of thewax formulation was loaded. This piston was poweredby a butane-fueled cordless nail gun. When the guntrigger was depressed, the piston rapidly shot an intactWax Dollop out of the barrel. Immediately after theshot, the barrel was automatically reloaded with ßow-able wax from an electric grease gun carried in abackpack. The pneumatic gun applicator was Þttedwith a laser sight, and it could Þre accurately at dis-tances �2 m.

The swipe applicator consisted of an electric greasegun (PowerLuber, Lincoln, St. Louis, MO) Þtted witha 1-m-long stainless steel pipe (6-mm internal diam-eter). A 3-cm-diameter metal disk at the end of thewand, created a “foot” that was placed against a treebranch. The trigger of this apparatus was depressed todispense the desired amount of ßowable wax. Using aswiping motion, a dollop was deposited on the branch.

The spatula applicator was a laboratory spatula witha 10- by 2-cm stainless steel blade. When the spatulawas dipped in a container of emulsion to a depth of 3cm, �2.5 g (3 ml) of product was consistently with-drawn. The loaded spatula was placed against a treebranch and then pulled downward, leaving a dollop onthe branch.

Times for application of dollops to a 0.2-ha portionof a mature mixed peach and plum (Prunus spp.)orchard (Michigan State University HorticulturalTeaching and Research, Viticulture and EnologyFarm, East Lansing, MI) by using these three appli-cators were compared with those to apply Confuse-OFM with a paint-marking gun and Isomate-M 100polyethylene tube dispensers by hand. The experi-ment was replicated four times and blocked by theperson making the application. All formulations wereapplied at a rate of 537 dispensers per hectare.


Statistical Analyses

The level of signiÞcance for all statistical tests was� � 0.05. Moth captures in pheromone traps were logtransformed (log[x � 1]), and shoot and fruit injurydata were arcsine transformed (arsine [sqrt x]) beforeanalysis. The transformed data were analyzed by anal-ysis of variance (ANOVA) for a randomized completeblock design. Means were separated using TukeyÕs test(SAS Institute 1999).

Moth captures in bucket traps were log transformed(log [x � 1]) before analysis. The numbers of maleand female moths caught in bucket traps in 2001 wasanalyzed with a paired t-test. A two-factor ANOVAfor a randomized complete block design was used toanalyze the numbers of male and female moths caughtin bucket traps in 2002; treatment and generation werethe two factors analyzed. Means were separated usingTukeyÕs test (SAS Institute 1999).

Too few females were caught in generation 1 in 2002to analyze the percentage of mated female data forthat generation. The percentage of mated female datafor generation 2 in both years was normally distributedwith equivalent variances. These untransformed datawere analyzed by ANOVA for a randomized completeblock design, followed by means separation withTukeyÕs test (SAS Institute 1999).

Dispenser application times using various applica-tors were normally distributed with equivalent vari-ances. The untransformed data were analyzed by

ANOVA for a randomized complete block design.Means were separated using TukeyÕs test (SAS Insti-tute 1999).

For pheromone release proÞle determinations,the amount of pheromone remaining in the dispens-ers was plotted over time and exponential curveswere Þtted to the data by using Microsoft Excel 2002(Microsoft, Redmond, WA). The primary objectivein Þtting curves to the data was to use these toaccurately calculate the release rate of pheromonefrom the dispensers at any point in time. To this end,obtaining the best curve Þt possible was essential. Insome cases, the best Þt to data from one formulationwas achieved with two exponential curves. Theequations for the Þtted curves were differentiated,and the resulting equation was used to calculatehow long dispensers continued to release phero-mone at a rate equal to or greater than the Roths-child (1975) threshold release rate of 5 mg/ha/h fordisruption of male G. molesta orientation to pher-omone traps. Although other authors have offeredestimates of the release rate of pheromone neces-sary per area for mating disruption of G. molesta tobe effective (6.25 mg/ha/h, Carde et al. 1977; 0.01mg/ha/h, Charlton and Carde 1981; 20 mg/ha/h,Audemard et al. 1989), the threshold release ratedetermined by Rothschild (1975) is most consistentwith the data gathered in the present studies. Toconvert release rates per dispenser to release rates

Fig. 1. The 2001 Þeld trial testing the efÞcacy of Confuse-OFM versus two other commercial G. molesta pheromonedispensers. (a) G. molesta caught in pheromone traps. Treatments labeled with the same letter, within a generation, are notsigniÞcantly different (TukeyÕs test; P � 0.05). (b) Percentage of peach shoots and fruit sampled with internal injury fromlarvae. For each of the evaluations, there were no signiÞcant differences between the treatments (TukeyÕs test; P � 0.05).Injuries for CheckMate OFM-F in generation 2 and at harvest were for three plots only (n � 4 for all other treatments).


per hectare, the amount of active ingredient appliedper hectare was taken as 74 g.

Results and Discussion

Confuse-OFM Trials

Efficacy. Two applications of Confuse-OFM (148 gAI/ha) were at least as effective as one application ofIsomate-M 100 (57 g AI/ha) and two applications ofCheckMate OFM-F (148 g AI/ha) in reducing G.molesta captures in pheromone traps (Fig. 1a). Al-though small numbers of moths were caught in allpheromone treatments in both generations, signiÞ-cantly fewer moths were caught in these than in theno-pheromone treatment (generation 1: F � 18.92,df � 3, P � 0.0003; and generation 2: F � 41.05, df �3, P � 0.0001). In both generations, equivalent num-bers of moths were caught in all pheromone treat-ments, indicating a similarly reduced ability of maleG.molesta to Þnd pheromone sources in those plots.

Shoot injury at the ends of generations 1 and 2 andfruit injury at harvest did not differ signiÞcantly acrossthe treatments (Fig. 1b) (generation 1 shoot: F� 0.58,df � 3, P� 0.64; generation 2 shoot: F� 0.43, df � 3,P� 0.73; and harvest fruit: F� 0.49, df � 3, P� 0.70).Although there was considerable variability in thepercentage of shoot injury quantiÞed in some of thetreatments, overall, the levels of injury recorded werevery low (Fig. 1b). The percentage of fruit injuryreported at harvest for all treatments was well belowthe 1% fruit injury threshold accepted by Michigangrowers.

In generation 2, the numbers of male and femaleG.molesta caught in bucket traps in the Confuse-OFMand no-pheromone treatments were not signiÞcantlydifferent (Table 1) (male: t � 1.64, df � 3, P � 0.20;and female: t� 0.49, df � 3, P� 0.66). Data gatheredfrom these traps were not useful in separating treat-ments. Atanassov et al. (2002) also found no signiÞcantdifferences in the numbers of male and female G.

molesta caught in bucket traps placed in plots treatedwith insecticide or with Isomate-M or Isomate-M 100pheromone dispensers.

There were both advantages and disadvantages totesting the efÞcacies of these formulations on com-mercial peach farms. On-farm trials permitted use ofrelatively large plots, thereby reducing the likelihoodof immigrating moths masking treatment effects.However, growers were unable to risk their high-valuefresh-market peaches; only one less insecticide spraywas applied in most pheromone plots versus the no-pheromone plots. However, applications of azinphos-methyl, the most efÞcacious insecticide for control ofG. molesta (Wise et al. 2002), in all cases, were eithereliminated or reduced from two to one in pheromone-treated plots versus the no-pheromone plots.Longevity. Pheromone release from Confuse-OFM

in the Þeld had Þrst-order kinetics (Fig. 2). The initialrelease rate was higher than desired; approximatelytwo thirds of the pheromone was released in the Þrst21 d. The high release rate of this formulation can beattributed to its physical shape after application. Therelease rate of compounds from such monolithic de-vices conforms to FickÕs law of diffusion, and it isstrongly inßuenced by the surface area and the thick-ness of the dispensing matrix (Fan and Singh 1989,Atterholt 1996). A thin formulation with a large sur-face area, such as Confuse-OFM, has a relatively highrelease rate and low longevity.

When Confuse-OFM was applied to tongue depres-sors and left to dry on a horizontal surface, the depositwas thicker than that realized under normal Þeld con-ditions and only covered approximately one third thearea. As deployed on the tongue depressors, the re-lease rate of pheromone would have remained greaterthan or equal to the threshold release rate of 5 mg/ha/h (Rothschild 1975) for 93 d, approximately thelongevity of Isomate-M 100, as stated on the productlabel. That this was an overestimation of the longevityof this formulation when it was applied to trees was

Table 1. Sum of G. molesta caught per liquid attractant-baited bucket trap per generation during the 2001 and 2002 field trialscomparing the efficacies of Confuse-OFM and Wax Dollops to those of two commercial G. molesta pheromone formulationsa

Yr Generation TreatmentMalesb,c

(mean � SE)Femalesb,c

(mean � SE)Percent females matedd,e

(mean � SE)

2001 2 No-pheromone 0.7 � 0.5 2.4 � 2.1Confuse-OFM 0.1 � 0.1 1.1 � 0.7

2002 1 No-pheromone 0.2 � 0.2 0.7 � 0.5 78 � 7Confuse-OFM 0.0 0.0Isomate-M 100 0.1 � 0.1 0.3 � 0.1 100 � 0Wax Dollops 0.0 0.1 � 0.1 100 � 0

2 No-pheromone 0.9 � 0.4 2.4 � 0.8 62 � 10Confuse-OFM 0.6 � 0.3 2.5 � 1.1 73 � 3Isomate-M 100 1.3 � 0.5 2.2 � 0.5 49 � 12Wax Dollops 0.3 � 0.3 0.8 � 0.3 67 � 24

a Bucket traps were placed only in no-pheromone and Confuse-OFM plots in 2001.b In both 2001 and 2002, the numbers of males and females captured in the different treatments were not signiÞcantly different (2001: paired

t-test; P � 0.05; 2002: TukeyÕs test; P � 0.05).c There were signiÞcant increases in the numbers of males and females caught in bucket traps in generation two vs generation one in 2002

(TukeyÕs test; P � 0.05).d Too few data were gathered in generation 1 in 2002 to analyze the percentage of females mated for that generation statistically.e There were no signiÞcant differences between treatments in the percentage of females captured that were mated during generation two

in 2002 (TukeyÕs test; P � 0.05).


borne out by the Þnding that shutdown of moth cap-tures in monitoring traps in Confuse-OFM plots in the2002 Þeld trials (see below) lasted only 77 d. A secondapplication of Confuse-OFM was necessary for sea-son-long control. The Confuse-OFM application tech-nique was modiÞed for the subsequent release rateexperiment to more truly mimic Confuse-OFM de-posits in the Þeld (see Developing Wax Dollopsabove).Drawbacks. Major deÞciencies of the Confuse-

OFM formulation were identiÞed during the 2001studies. Although Confuse-OFM was an effective mat-ing disruption product, the need for two applicationsof this formulation for season-long control of G. mo-lesta was a major drawback. Pheromone is costly; al-most three times as much pheromone was necessaryfor season-long control of G. molesta with Confuse-OFM as with Isomate-M 100 (148 g AI/ha versus 57 gAI/ha). Hand-applying dispensers is time-consumingand expensive; performing this process twice per sea-son raises the cost of a mating disruption program.Moreover, Confuse-OFM application was tedious. Be-

cause this formulation was so liquid, care and timewere necessary to successfully apply it to tree bark andto minimize the amount that dripped onto the ground.Furthermore, the applicators provided to apply theemulsion were inadequate. Plastic squirt bottles andpaint-marking guns were not designed to apply thewax material; they broke or clogged after only a fewhours of use.

Developing Wax Dollops

Thickened emulsiÞed wax formulations showedconsiderable promise for commercialization asG.mo-lesta disruptants. The release proÞles of Wax Dollopsunder laboratory conditions were Þrst order (Fig. 3).However, more viscous formulations yielded less con-cave release proÞles. Emulsions B and C had similarrelease proÞles and maintained pheromone releaserates �5 mg/ha/h (Rothschild 1975) for 113 and 116 d,respectively, twice as long as Confuse-OFM (56 d). Inthis experiment, the Confuse-OFM deposits closelymimicked the Confuse-OFM deposits applied to trees.

Fig. 2. Release proÞle of (Z)8-12:Ac from Confuse-OFM dispensers aged in the Þeld. Due to the application method,dispenser longevity is inßated over that for material deployed on trees (see text).

Fig. 3. Release proÞle of (Z)8-12:Ac from Confuse-OFM and three experimental wax emulsions aged in a laboratory fumehood. Regression equations are as follows: Confuse-OFM: days 0Ð21, y � 120.9e�0.068x, r2 � 0.98, days 21�, y � 64.4e�0.045x,r2 � 0.97; emulsion A: y � 121.2e�0.031x, r2 � 0.95; emulsion B: y � 126.3e�0.024x, r2 � 0.98; and emulsion C: y � 137.6e�0.024x,r2 � 0.97.


Evaluation of Wax Dollops

Efficacy.Wax Dollops were as effective as Confuse-OFM and Isomate-M 100 for G. molesta control. Al-though large numbers of moths were caught in theno-pheromone treatments in both G. molesta gener-ations, few or no moths were caught in the phero-mone-treated plots during the trial (Fig. 4a). In bothgenerations, signiÞcantly fewer moths were caught inpheromone traps in all pheromone-treated versus theno-pheromone plots (generation 1: F � 17.7, df � 3,P � 0.0004; and generation 2: F � 41.1, df � 3, P �0.0001), and there were no signiÞcant differences inthe numbers of moths caught in the three pheromonetreatments.

Data from virgin female traps supported those frompheromone traps. Although male moths were caughtin virgin female traps placed in no-pheromone plotsduring the trial (males per trap per day, mean � SE,generation 1: 0.2 � 0.1; generation 2: 0.7 � 0.5), nomales were caught in virgin female traps placed in anyof the pheromone-treated plots. Thus, pheromonetraps provided the more sensitive measure of the abil-ity of male G. molesta to Þnd pheromone sources inplots under mating disruption. Virgin female trapswere more labor-intensive to set up and maintain, andthey provided less information than was obtained withpheromone traps.

Although levels of injury to shoots and fruit weregenerally higher in 2002 than in 2001 (Figs. 4b versus1b), trends remained the same. As in 2001, there was

considerable variation in the injury quantiÞed in someof the treatments and no signiÞcant differences amongthe treatments for any of the injury evaluations con-ducted (generation 1 shoot: F� 0.74, df � 3, P� 0.56;generation 2 shoot: F � 1.75, df � 3, P � 0.23; andharvest fruit: F� 0.81, df � 3, P� 0.52). Two plots hadharvest fruit injuries in excess of 1% (�1% fruit injuryis considered excessive by Michigan growers and pro-cessors): the no-pheromone plot on farm 5 had 1.8%fruit injury and the Confuse-OFM plot on farm 1 had1.2% injury. High levels of larval injury along someborders of those plots, but not others suggested matedfemales immigrated from nearby abandoned appleorchards known to harbor large populations of G.molesta.

Whereas in 2001, bucket traps were only placed intheConfuse-OFMandno-pheromoneplotsduring thesecond ßight ofG. molesta, in 2002, bucket traps wereplaced in all plots before the Þrst ßight. Nevertheless,the data were consistent in both years (Table 1). Thenumbers of male and female moths caught in buckettraps in the three pheromone treatments and the no-pheromone treatment were not signiÞcantly different(male: F� 2.49, df � 3, P� 0.09; and female: F� 2.78,df � 3, P� 0.07). However, more moths caught werecaught in bucket traps in generation 2 versus gener-ation 1 (male:F� 19.71, df � 1,P� 0.0002; and female:F� 46.35, df � 1,P� 0.0001). The interaction betweentreatment and generation was not signiÞcant (male:F � 0.98, df � 3, P � 0.42; and female: F � 1.77, df �

Fig. 4. The 2002 Þeld trial testing the efÞcacy of Wax Dollops, Confuse-OFM, and Isomate-M 100. (a)G. molesta caughtin pheromone traps. Treatments labeled with the same letter, within a generation, are not signiÞcantly different (TukeyÕs test;P � 0.05). (b) Percentage of peach shoots and fruit sampled with internal injury from larvae. For each of the evaluations,there were no signiÞcant differences between the treatments (TukeyÕs test; P � 0.05).


3, P � 0.18). In addition, the percentages of femalesthat were mated in the no-pheromone and phero-mone-treated plots in generation 2 were not signiÞ-cantly different (generation 2: F � 0.82, df � 3, P �0.51). Too few females were captured for statisticalanalysis of female mating for generation 1.

Rothschild (1981) stated that bucket traps seemedto be more attractive to mated females than to virginfemales. He found small, but signiÞcant reductions, inthe percentages of females mated in pheromone-treated plots by using this technique. However, suchdifferences were not identiÞed in the current exper-iment. Atanassov et al. (2002) also found no signiÞcantdifferences in the percentages of mated female G.molesta caught in bucket traps placed in no-phero-mone versus pheromone-treated plots. Althoughthese data do not reveal treatment differences, theyare evidence that moth populations in these plots wereequivalent.

Growers primarily relied on the pyrethroids, per-methrin or esfenvalerate, forG. molesta control in theno-pheromone plots and for supplemental control ofG. molesta in the pheromone plots. As in the 2001Confuse-OFM efÞcacy trial, insecticide treatmentswere generally only reduced by one spray in the pher-omone-treated plots versus the no-pheromone plots.Nevertheless, the high numbers of moths caught inpheromone traps in the no-pheromone plots (Fig. 4a)and equivalent numbers of moths caught in buckettraps placed in all treatments in 2002 (Table 1) indi-cated the presence of relatively large G. molesta pop-ulations in all plots. Even under relatively high pestpressure, high pheromone and virgin female trap shut-down was successfully achieved in all pheromone-treated plots. Thus, Wax Dollops were as effective asthe other commercially available dispensers testedin preventing G. molesta from Þnding pheromonesources.Longevity.Emulsion C dollops released pheromone

for twice as long as Confuse-OFM in the laboratory(Fig. 3). As judged by the similar slopes of the Þtted

curves, adding adhesive to emulsion C1 did not alterthe release proÞle of pheromone from the resultingdollops (Fig. 5). The rate of pheromone release from3-ml dollops in the Þeld remained �5 mg/ha/h (Roth-schild 1975) for �85 d, which is close to the 90-dlifetime of Isomate-M 100, as reported on the productlabel.

Moth captures over the course of the season pro-vided a second means of assessing the longevity of thedisruption formulations. The average numbers of G.molesta caught per pheromone trap per half weekthroughout the season in the 2002 plots are shown inFig. 6. After the Þrst applications of the pheromoneformulations (19 April), moth captures were substan-tially inhibited or completely shut down in the plotstreated with dollops until 9 August, 112 d after appli-cation. Trap catch shutdown was maintained in theIsomate-M 100 plots until 6 August, 109 d after appli-cation, anduntil 5 July in theConfuse-OFMtreatment,77 d after application. Confuse-OFM was reapplied on8 July and trap catch shutdown was maintained untilharvest. From these data, it can be concluded that 3-mlWax Dollops remained effective for a period equiva-lent to Isomate-M 100 and as much as twice as long asConfuse-OFM, which corroborates the conclusionreached from the laboratory release rate data.

Based on trap catch shutdown, the longevity of WaxDollops was �27 d longer than the estimate based onmaintenance of release rates �5 mg/ha/h (Rothschild1975). The manufacturer-estimated longevity of Iso-mate-M 100 is 90 d. This is 19 d less than the longevityobtained in southwestern Michigan in 2002. The Þrstapplication of Confuse-OFM lasted an unexpectedlylong time, 77 d. The greater than expected longevityof the Þrst applications of all pheromone dispensers inthis study can be explained by low temperatures inApril andMay,when thedispensers released lesspher-omone than during the hotter summer (Fan and Singh1989, Atterholt 1996).

A zero-order (steady) release rate is generally con-sidered desirable for a pheromone dispenser. How-

Fig. 5. Release proÞle of (Z)8-12:Ac from Wax Dollops with and without adhesive aged in the Þeld. Regression equationsare as follows: Emulsion C1, no adhesive: days 0Ð42: y � 119.7e�0.037x, r2 � 0.93, days 42�: y � 49.6e�0.016x, r2 � 0.82; emulsionC2, low adhesive: days 0Ð42: y � 117.5e�0.046x, r2 � 0.98, days 42�: y � 53.1e�0.024x, r2 � 0.98; emulsion C3, high adhesive:days 0Ð42, y � 114.4e�0.038x, r2 � 0.98, days 42�, y � 57.1e�0.021x, r2 � 0.95.


ever, monolithic dispensers, such as Wax Dollops,have Þrst-order release kinetics (Fan and Singh 1989);their release rate diminishes over time. This higherinitial release rate might actually be beneÞcial, be-cause it coincides with early spring, when tempera-tures are lower and foliage that is not fully ßushed hasa reduced capacity to absorb pheromone and serve asa secondary release site (Sauer and Karg 1998, Gut etal. 2004).Application. The times required to hand-apply a

pheromone formulation to 0.2 ha of a mixed peachand plum orchard ranged from 41 min/ha to 1 h 15min/ha (Fig. 7). Applying Wax Dollops with thespatula applicator was faster than any other methodand nearly twice as fast as hand-applying Isomate-M

100 polyethylene tube dispensers (F � 32.86, df �4, P � 0.0001). Application time for hand-appliedformulations was minimized when the person ap-plying the dispensers did not stop walking either toapply the material or prepare for the next applica-tion. This was only possible with the spatula. Afurther advantage of the spatula applicator was itssimplicity; it never malfunctioned. During Þeld tri-als, all other emulsiÞed wax applicators experiencedsome equipment failures (these were not includedin the application times of Fig. 7). Furthermore,virtually no emulsion was wasted when dollops wereapplied with the spatula; emulsion dripping fromnozzles or not hitting the target tree resulted insome waste when dollops were applied with the

Fig. 6. Mean number ofG.molesta caught per pheromone trap per half week in all treatments at each sampling date duringthe 2002 Þeld trial comparing the efÞcacy of Wax Dollops versus Confuse-OFM and Isomate-M 100. Most plots were harvestedin early to mid-August. Note that the left y-axis applies to pheromone treatments, whereas the differently scaled right y-axisapplies to the no-pheromone treatment.

Fig. 7. Comparison of time necessary to apply 1) Wax Dollops by using the pneumatic gun, swipe, or spatula applicators;2) Confuse-OFM using a paint-marking gun; and 3) Isomate-M 100 polyethylene tube dispensers by hand to 0.2 ha of mixedpeaches and plums. Bars labeled with the same letter are not signiÞcantly different (TukeyÕs test; P � 0.05). Application ofWax Dollops with the pneumatic gun was replicated three times, n � 4 for all other applicators.


other applicators. The spatula method of applicationis highly recommended over the other methods forapplying emulsiÞed wax dispensers in mating dis-ruption systems similar to G. molesta, where dis-pensers need not be placed high in the canopy (deLame and Gut 2006). Where high placement is re-quired [e.g., Cydia pomonella (L.), Weissling andKnight 1995], a more sophisticated and specializedapplicator may be justiÞed.Commercialization. EmulsiÞed wax dispensers

consist mostly of wax and water. A by-product ofpetroleum reÞning, parafÞn wax is readily availableand inexpensive (Bennett 1975). Preparation of waxemulsion does not require highly specialized equip-ment, and it can easily be scaled up to produce largebatches with minimal labor. Thus, commercial pro-duction of wax emulsions should be cheaper than forother hand-applied formulations currently on themarket.

Building on the original work of Atterholt (1996)and colleagues (Atterholt et al. 1998, Delwiche et al.1998), the current research set in place the compo-nents necessary and sufÞcient for a new line of pher-omone-based pest-control products as effective as thebest currently on the market. Beyond cost, emulsiÞedwax offers considerable opportunity for product ßex-ibility. For example, insecticides have been incorpo-rated into emulsiÞed wax to yield effective attracticideformulations (www.iscatech.com). Furthermore, be-cause they are ßowable, adhesive, and dispersible,emulsiÞed waxes have the potential to be applied at awide range of deposit sizes and spatial distributions. Asshown in the current work, emulsiÞed wax can beapplied as dollops of sufÞcient size to provide season-long disruption with only one application. Moreover,emulsiÞed wax can be widely dispersed to providecoverage akin to high-density disruption formulationssuch as chopped Þbers or ßakes (Stelinski et al. 2005).After the completion of these studies, in 2003, ISCATechnologies, Inc. (Riverside, CA) licensed the waxemulsion patent. It has conducted extensive tests ofthis technology and continues to adapt it for a varietyof pest and cropping systems (www.iscatech.com).ISCAÕs Specialized Pheromone & Lure ApplicationTechnology (SPLAT) has been granted a federal reg-istration for G. molesta control by the U.S. Environ-mental Protection Agency and was made available asSPLAT OFM 30M-1 for commercial use in 2006.

Acknowledgments

We thank Katie Bosch, Clarrissa Chavez, Chad Hipshier,Mathew Jolman, Emese Karacsonyi, Creela Overton, TravisReed, Vicki Walter, Piera Giroux, Mike Haas, Peter McGhee,and John Wise for assistance. Undergraduate students ErikArbut, Lindsey Brown, and Larry Morden developed thepneumatic gun under the tutelage of Michigan State Uni-versity Agricultural Engineers Richard Ledebuhr and GaryVan Ee, who also designed and built the swipe applicator.Randy Bjorge, Jim Calderwood, Randy Willmeng, and Rod-ney Winkle kindly made the research plots available on theirfarms. We also thank Nicolas Ellis, Piera Giroux, Rufus Isaacs,and Lukasz Stelinski for valuable review of this manuscript.

Funding for this research was provided by Gowan Co., theMichigan Agricultural Experiment Station, and the USDAÐCSREES Special Fruit Grant Program. A Michigan StateUniversity Plant Science Fellowship and a National ScienceFoundation Graduate Research Fellowship to F.M.d.L. aregratefully acknowledged.

References Cited

Atanassov,A., P.W.Shearer,G.Hamilton, andD.Polk. 2002.Development and implementation of a reduced riskpeach arthropod management program in New Jersey. J.Econ. Entomol. 95: 803Ð812.

Atterholt, C. A. 1996. Controlled release of insect sex pher-omones from sprayable, biodegradable materials for mat-ing disruption. Ph.D. dissertation, University of Californiaat Davis, Davis, CA.

Atterholt, C. A.,M. J.Delwiche, R. E. Rice, and J.M.Krochta.1998. Study of biopolymers and parafÞn as potential con-trolled-release carriers for insect pheromones. J. Agric.Food Chem. 46: 4429Ð4434.

Audemard, H., C. Leblon, U. Neumann, and G. Marboutie.1989. Bilan de sept annees dÕessais de lutte contre latordeuse orientale du pecher Cydia molesta Busck (Lep.,Tortricidae) par confusion sexuelle des males. J. Appl.Entomol. 108: 191Ð207.

Bennett, H. 1975. Industrial waxes, vols. 1 and 2. ChemicalPublishing Company, New York.

Carde, R. T., T. C. Baker, and P. J. Castrovillo. 1977. Dis-ruption of sexual communication in Laspeyresiapomonella (codling moth),Grapholitha molesta (orientalfruit moth) and G. prunivora (lesser appleworm) withhollow Þber attractant sources. Entomol. Exp. Appl. 22:280Ð288.

Charlton, R. E., and R. T. Carde. 1981. Comparing the ef-fectiveness of sexual communication disruption in theoriental fruit moth (Grapholita molesta) using differentcombinations and dosages of its pheromone blend.J. Chem. Ecol. 7: 501Ð508.

de Lame, F. M., and L. J. Gut. 2006. Effect of monitoringtrap and mating disruption dispenser application heightson captures of maleGrapholita molesta (Busck; Lepidop-tera: Tortricidae) in pheromone and virgin female-baitedtraps. Environ. Entomol. 35: 1058Ð1068.

Delwiche, M., C. Atterholt, and R. Rice. 1998. Spray appli-cation of parafÞn emulsions containing insect phero-mones for mating disruption. Trans. ASAE 41: 475Ð480.

Delwiche, M., J. M. Krochta, R. E. Rice, and C. Atterholt.1999. Aqueous emulsion comprising biodegradable car-rier for insect pheromones and methods for controlledrelease thereof. U.S. Patent 6,001,346.

Fan, L. T., and S. K. Singh. 1989. Controlled release: a quan-titative treatment. Springer, New York.

George, J. A. 1965. Sex pheromone of the oriental fruit mothGrapholitamolesta(Busck). Can. Entomol. 97: 1002Ð1007.

Gut, L. J., L. L. Stelinski, D. R. Thomson, and J. R. Miller.2004. Behaviour-modifying chemicals: prospects andconstraints in IPM, pp. 73Ð121. InO. Koul, G. S. Dhaliwal,and G. W. Cuperus [eds.], Integrated pest management:potential, constraints, and challenges. CABI Publishing,Cambridge, MA.

Jackson, G. J. 1989. The development and marketing of apheromone system, pp. 281Ð293. In A. R. Justum andR.F.S. Gordon [eds.], Insect pheromones in plant pro-tection. Wiley, New York.

McNair, H. M., and J. M. Miller. 1998. Basic gas chroma-tography. Wiley, New York.


Meissner, H. E., C. A. Atterholt, J. F. Walgenbach, and G. G.Kennedy. 2000. Comparison of pheromone applicationrates, point source densities, and dispensing methods formating disruption of tufted apple bud moth (Lepidop-tera: Tortricidae). J. Econ. Entomol. 93: 820Ð827.

Plimmer, J. R., and M. N. Inscoe. 1978. Insect pheromones:some chemical problems involved in their use and de-velopment, pp. 249Ð260. In F. J. Ritter [ed.], Chemicalecology: odour communication in animals: scientiÞc as-pects, practical uses, and economic prospects. Elsevier/North-Holland Biomedical Press, New York.

Plimmer, J. R. 1981. Formulation and regulation: con-straints on the development of semiochemicals for insectpest management, pp. 403Ð420. In E. R. Mitchell [ed.],Management of insect pests with semiochemicals: con-cepts and practice. Plenum, New York.

Pree, D. J., R. M. Trimble, K. J. Whitty, and P. M. Vickers.1994. Control of oriental fruit moth by mating disruptionusing sex pheromone in the Niagara Peninsula, Ontario.Can. Entomol. 126: 1287Ð1299.

Rice, R. E., and P. Kirsch. 1990. Mating disruption of ori-ental fruit moth in the United States, pp. 193Ð211. InR. L.Ridgway, R. M. Silverstein, and M. N. Inscoe [eds.], Be-havior-modifying chemicals for insect management: ap-plications of pheromones and other attractants. MarcelDekker, New York.

Rothschild, G.H.L. 1975. Control of oriental fruit moth(Cydia molesta (Busck) (Lepidoptera, Tortricidae))with synthetic female pheromone. Bull. Entomol. Res.65: 473Ð490.

Rothschild, G.H.L. 1979. A comparison of methods of dis-pensing synthetic sex pheromone for the control of ori-ental fruit moth, Cydia molesta (Busck) (Lepidoptera:Tortricidae), in Australia. Bull. Entomol. Res. 69: 115Ð127.

Rothschild, G.H.L. 1981. Mating disruption of lepidopter-ous pests: current status and future prospects, pp. 207Ð228. In E. R. Mitchell [ed.], Management of insect pestswith semiochemicals. Plenum, New York.

SAS Institute. 1999. SAS OnlineDoc, version 8. SAS Insti-tute, Cary, NC.

Sauer, A. E., and G. Karg. 1998. Variables affecting phero-mone concentration in vineyards treated for matingdisruption of grape vine moth Lobesia botrana. J. Chem.Ecol. 24: 289Ð302.

Shorey, H. H., and R. L. Hale. 1965. Mass rearing of thelarvae of nine noctuid species on a simple artiÞcial me-dium. J. Econ. Entomol. 58: 522Ð524.

Siddall, J. B. 1978. Commercial production of insect pher-omonesÑproblems and prospects, pp. 389Ð402. In F. J.Ritter [ed.], Chemical ecology: odour communication inanimals: scientiÞc aspects, practical uses, and economicprospects. Elsevier/North-Holland Biomedical Press,New York.

Stelinski, L. L., L. J. Gut, R. E. Mallinger, D. Epstein, T. P.Reed, and J. R. Miller. 2005. Small plot trials document-ing effective mating disruption of oriental fruit moth byusing high densities of wax-drop pheromone dispensers.J. Econ. Entomol. 98: 1267Ð1274.

Trimble, R.M.,D. J. Pree, andN. J. Carter. 2001. Integratedcontrol of oriental fruit moth (Lepidoptera: Tortricidae)in peach orchards using insecticide and mating disrup-tion. J. Econ. Entomol. 94: 476Ð485.

Trimble, R. M., D. J. Pree, E. S. Barszcz, and N. J. Carter.2004. Comparison of a sprayable pheromone formulationand two hand-applied pheromone dispensers for use inthe integrated control of Oriental fruit moth (Lepidop-tera: Tortricidae). J. Econ. Entomol. 97: 482Ð489.

Weatherston, I. 1990. Principles of design of controlled-re-lease formulations, pp. 93Ð112. In R. L. Ridgway, R. M.Silverstein, and M. N. Inscoe [eds.], Behavior-modifyingchemicals for insect management. Marcel Dekker, NewYork.

Weissling, T. J., andA. L. Knight. 1995. Vertical distributionof codling moth adults in pheromone-treated and un-treated plots. Entomol. Exp. Appl. 77: 271Ð275.

Wise, J., P. Bills, M. Sklapsky, A. Swagart, andM.Haas. 2002.Extension bulletin E-154: fruit spraying calendar. Mich-igan State University Extension, East Lansing, MI.

Received 19 September 2006; accepted 4 March 2007.


Documents

H E Development and Evaluation of an Emulsiﬁed Parafﬁn …The release proÞles of three experimental emulsi-Þed wax formulations and Confuse-OFM were deter-mined in the laboratory