Vertical distribution of codling moth adults in pheromone-treated and untreated plots

The vertical distribution of codling moth,Cydia pomonella (L.) within pheromone-treated and untreated apple and pear orchard canopies was determined using tethered virgin females, unbaited sticky traps, and blacklight observation of released moths. Mating of virgin females tethered at various heights in untreated orchard canopies increased with placement height from 1–4 m. Application of pheromone dispensers for mating disruption at 2 and 4 m above the ground greatly decreased mating. Greatest capture of males and females on unbaited sticky traps occurred at mid- and upper-canopy heights. Total capture of males and females in pheromone-treated plots was not statistically different than in untreated plots. The percentage of mated females captured on sticky traps did not vary with trap height or pheromone treatment. Released moths marked with flourescent powder and observed at dark with a blacklight indicated that moths are primarily distributed high in the canopy. However, males shifted to a position lower in the canopy when pheromone dispensers were placed 2.1 m above the ground. Results suggest that pheromone dispensers be placed in the upper canopy for optimal disruption of codling moth mating.     

Pheromone pre-exposure and mating modulate codling moth (Lepidoptera: Tortricidae) response to host plant volatiles

Abstract 1 Two codling moth Cydia pomonella kairomonal attractants, ethyl (E,Z)‐2,4‐decadienoate (pear ester) and (E)‐β‐farnesene, were tested in an insecticide‐sprayed apple orchard and an orchard treated for mating disruption with synthetic pheromone (E,E)‐8,10‐dodecadienol (codlemone). Male captures with pear ester were higher in the pheromone‐treated than in the insecticide‐treated orchard, whereas captures with (E)‐β‐farnesene were not different. Subsequent wind tunnel experiments confirmed that pre‐exposure to sex pheromone codlemone increased the behavioural response of codling moth males to pear ester. This supports the idea that male attraction to the plant volatile pear ester and sex pheromone codlemone is mediated through the same sensory channels. 2 Pear ester is a bisexual codling moth attractant and even captures of female moths were significantly increased in the pheromone‐treated orchard. In the laboratory wind tunnel, pheromone pre‐exposure had no effect on female response to pear ester, but significantly more mated than unmated codling moth females flew upwind towards a pear ester source. Differences in mating status in insecticide‐treated vs. pheromone‐treated orchards may thus account for the differences in female trap captures with pear ester. 3 These findings are important with respect to monitoring of codling moth with pear ester in mating disruption orchards. They also emphasize the importance of host plant volatiles in pheromone‐mediated mating disruption, which has been neglected to date.     

Development of pheromone-based mating disruption for control of the eye-spotted bud moth, Spilonota ocellana

The potential for pheromone-based mating disruption of eye-spotted bud moth (ESBM), Spilonota ocellana (Denis & Schiffermüller) (Lepidoptera: Tortricidae), in apple orchards in the Okanagan Valley of British Columbia was examined in small-plot trials. In a preliminary experiment, treatment of the orchard atmosphere with a 99:1 blend of Z8-tetradecenyl acetate (Z8-14:OAc) and Z8-tetradecenyl alcohol (Z8-14:OH) completely inhibited captures of male ESBM in pheromone-baited traps, but treatment with Z8-14:OAc alone did not. Therefore, all subsequent trials used the two-component blend as a disruptant. Mean catches of male ESBM in traps baited with 0.1, 1, 10, or 20 mg of 99:1 Z8-14:OAc and Z8-14:OH were significantly reduced (81–97%) in pheromone-treated plots relative to similar traps placed in control plots. In both control and treated plots, there was a significant positive relationship between trap bait dose and trap catch. In pheromone-treated plots, this suggests that high doses of trap baits over-ride the camouflage effect of disruption or overcome the effect of sensory adaptation and habituation. The number of virgin-female baited traps capturing at least one male ESBM was reduced by 96%, and mating of virgin females on mating tables was reduced by 95% in plots treated with the two-component pheromone. The total amount of Z8-14:OAc released from pheromone disruption dispensers during the latter field trials was estimated to average 6.4 g ha^-1 over 11 days or 26.4 mg ha^-1 h^-1. The low levels of Z8-14:OH released from disruption dispensers could not be estimated by GC analysis. Dispensers loaded with a 99:1 blend of Z8-14:OAc and Z8-14:OH were highly attractive to males in baited traps, indicating that they have the potential to induce false trail following.     

Pheromone-mediated mating disruption of Choristoneura rosaceana: is the most attractive blend really the most effective?

An attractive four-component pheromone blend containing a major component Z11-tetradecenyl acetate, and three minor components, E11-tetradecenyl acetate, Z11-tetradecenyl alcohol, and Z11-tetradecenyl aldehyde was tested as a mating disruptant against western Canadian populations of the obliquebanded leafroller, Choristoneura rosaceana (Harris) (Lepidoptera: Tortricidae), in organic apple orchards in British Columbia. Efficacy of this four-component blend was compared to that of partial pheromone blends containing the major component plus one or two minor components. A trapping experiment confirmed that, Conrel® fibre disruption dispensers containing the four-component blend were more attractive than disruption dispensers containing the two- or three-component partial blends. A small-plot protocol was followed to compare atmospheric treatments with these blends as mating disruptants at a release rate of 10 mg ha–1 h–1 and from 1000 dispensers ha–1. Mechanisms of mating disruption, such as false-trail following and camouflage of pheromone plumes, that may be evoked to a greater degree by an attractive blend, did not appear to augment the effectiveness of mechanisms invoked by the less attractive blends, as the proportion of mating among tethered females was equal in plots treated with these blends and was reduced by 85–90% compared to the nontreated control. When the four-component pheromone blend was tested at different release rates, mating disruption in small plots began to break down at a release rate of 1.3 mg ha–1 h–1 using a dispenser density of 1000 ha–1. Above 1.3 mg ha–1 h–1 there was no dose response in release rates tested and at release rates below this dose the proportion of tethered females mating was the same as in the nontreated control. The four-component pheromone blend was tested against, and found to be no more effective than, the two-component partial blend at the threshold release rate of 1.3 mg ha–1 h–1 when it was released from 1000 or 250 disruption dispensers. Our results suggest that disruption mechanisms evoked by the attractive blend did not enhance the mating disruption effect provided by the simple blend, therefore a two-component blend may be useful in an operational mating disruption program for C. rosaceana.     

Interference with the mate-finding communication system of the Chinese tortrix Cydia trasias (Lep., Olethreutidae) using synthetic sex pheromones

Abstract: Interference with the mate-finding communication system of Cydia trasias (Meyrick) using sex pheromone dispensers (60% E8,E10-dodecadienyl acetate and 40% E8,E10-dodecadien-1-ol, 0.5 mg/dispenser) was investigated in three plots of the Chinese scholar-tree, Sophora japonica L., in Beijing, China, in 2000. Treatments were evaluated by pheromone-baited traps, caged virgin females, pupating and hibernating populations on tree trunks, and assessment of larval damage in petioles and seed pods. Six to eight natural rubber septum dispensers were placed in each tree at the pheromone-treated plots at three separate periods: at the beginning of overwintering generation flight, the first- and the second-generation flights. Application of pheromone dispensers reduced the incidence of mating of virgin females in treated plots relative to those in the control plots. Pheromone-baited trap catches were lowered on average by 96%, suggesting a high level of disruption. Average larval density on tree trunks was significantly lower in the pheromone-treated plots than in the untreated control plots. The mean percentage of Chinese scholar-tree petioles infested with first- and second-generation larvae, and seed pods infested with third-generation larvae was significantly greater in untreated control plots than in pheromone-treatment plots. These results suggest that disruption of pheromone-based communication in C. trasias is prospective, with synthetic sex pheromone on trees in urban environments.     

Simultaneous mating disruption of two Grapholita species in apple orchards

Two Grapholita species (G. molesta and G. dimorpha) cause serious losses in apple production by means of direct fruit damage and destruction. These two congeners occurred at similar seasons in the same orchards. Furthermore, the two species occurred in similar population sizes in apple orchards, though G. molesta occurred much more in total occurrence density than did G. dimorpha in a pear orchard. The two species share two major sex pheromone components, (Z)-8-dodecenyl acetate (Z8-12:Ac) and (E)-8-dodecenyl acetate (E8-12:Ac), but differ with regard to the relative mixture ratio necessary to create conditions of maximal attraction. To develop a simultaneous mating disruption (SMD), a mass ratio of 95:5 of Z8-12:Ac and E8-12:Ac was selected due to its high cross-calling activity and subsequent high mating disruption against both species. When the mixture was applied to orchards, it resulted in significant mating disruption against both species. However, mating disruption efficacy was slightly higher in G. dimorpha than in G. molesta. Application dose and dispenser type affected efficacy duration of SMD. In addition, the high density occurrence of G. molesta significantly reduced the SMD efficacy. Using a wax-type of dispenser, an application of SMD in 100?g per hectare dispersed in early spring recorded >90% mating disruption efficacy through the entire growing season against both Grapholita species.     

Improved monitoring of female codling moth (Lepidoptera: Tortricidae) with pear ester plus acetic acid in sex pheromone-treated orchards

The performance of clear delta traps baited with 3.0 mg of pear ester, ethyl (E,Z)-2,4-decadienoate, and 5.0 ml of acetic acid in separate lures was compared with orange delta traps baited with a single lure containing 3.0 mg of both pear ester and the sex pheromone, (E,E)-8,10-dodecadien-1-ol (codlemone) for codling moth, Cydia pomonella (L.), in apple, Malus domestica (Borkhausen). Residual analyses and field tests demonstrated that both the pear ester and acetic acid lures were effective for at least 8 wk. The two trap-lure combinations caught a similar number of total moths in an orchard treated with sex pheromone dispensers during short-term trials in 2008. However, the mean catch of female moths was significantly higher and male moths significantly lower in clear traps baited with pear ester and acetic acid versus orange traps baited with pear ester and codlemone. Season-long studies were conducted with these two trap-lure combinations in orchards treated with (n = 6) and without (n = 7) sex pheromone dispensers during 2009. The two trap-lure combinations caught similar numbers of moths in dispenser-treated orchards. In contrast, total catch was significantly higher (>2-fold) in the orange compared with the clear traps in untreated orchards. The clear caught >6-fold more females than the orange trap in both types of orchards. These studies suggest that deploying clear delta traps baited with pear ester and acetic acid can be an effective monitoring tool for female codling moth and an alternative to codlemone-baited traps in sex pheromone-treated orchards.     

Mating disruption of Lasioderma serricorne (Coleoptera: Anobiidae) in stored product habitats using the synthetic pheromone serricornin

Cigarette beetles, Lasioderma serricorne (F.) (Coleoptera: Anobiidae), cause significant damage to the multibillion dollar food and tobacco industries worldwide each year. A non‐insecticidal alternative to manage L. serricorne is the application of mating disruption, in which high levels of synthetic sex pheromone are released to create an atmosphere that results in males failing to mate females, thereby causing population suppression or extinction. The reported work used synthetic serricornin, the predominant sex pheromone of L. serricorne, in mating disruption trials conducted in selected food‐ and feed‐processing facilities in South Carolina during 2010 and 2011. Mills subjected to mating disruption trials were monitored using oviposition cups filled with larval food and pheromone traps for males that contained monitoring lures. Immediately after deployment of mating disruption dispensers, trap captures declined significantly and indicated a reduction in population levels, that is, there was ‘trap shutdown’. A significant reduction was observed in numbers of adult beetles caught in the traps 8 weeks before and 8 weeks after treatment in both years. Beetle numbers from pheromone traps in untreated buildings remained at similar levels or increased after the time of mating disruption deployment in treated buildings. The numbers of adults that emerged from oviposition food cups were generally low and varied irregularly in treated and untreated buildings and were determined to be of little value for assessing treatment effects on reproduction. These initial field studies in the USA suggest that release of the synthetic sex pheromone of L. serricorne for mating disruption can significantly inhibit proper orientation behaviour of male L. serricorne to females and may lead to pest population decline from mating disruption.     

Sex pheromone of Argyrotaenia pomililiana (Lepidoptera: Tortricidae), a leafroller pest of apples in Argentina

Sex pheromone gland extracts of Argyrotaenia pomililiana Trematerra & Brown females contained seven 14-chain compounds, the Z and E isomers of 11-tetradecenyl acetate, 11-tetradecen-1-ol, and 11-tetradecenal, respectively, together with tetradecyl acetate. In field trapping tests, a 100:5 blend of Z11-14:Ac and Z11-14:Al was shown to be suitable for detection and monitoring of A. pomililiana. This species-specific lure will facilitate the use of mating disruption against codling moth, Cydia pomonella (L.), in Argentine fruit orchards.     

Variation in sex pheromone composition in large fruit-tree tortrix Archips podana Scop. (Lepidoptera: Tortricidae)

Variation in sex pheromone composition was studied in large fruit-tree tortrix. The pheromone contained cis-11-tetradecenyl acetate and trans-11-tetradecenyl acetate as macrocomponents as well as microcomponents cis-11-tetradecenol and trans-11-tetradecenol with the prevalence of cis-11-tetradecenyl acetate and cis-11-tetradecenol. The pheromone composition depended in part on the genotype of the male parent. Inbreeding increased the proportion of trans-11-tetradecenyl acetate and trans-11-tetradecenol.     

Comparison of pheromone-mediated mating disruption and conventional insecticides for management of tufted apple bud moth (Lepidoptera: Tortricidae)

Large-plot studies were used to compare pheromone-mediated mating disruption and conventional insecticide applications for management of tufted apple bud moth, Platynota idaeusalis (Walker), in North Carolina in 1993 and 1994. Pheromone trap catches were reduced in mating disruption blocks, and traps placed in the lower stratum of the canopy had a higher level of trap capture reduction compared with traps placed in the upper stratum. First-generation tufted apple bud moth exposure to either pheromones for mating disruption or insecticides affected second generation pheromone trap catches in the lower and upper canopy. More second generation male moths were caught in pheromone traps placed in the upper compared with the lower canopy in blocks treated with pheromones for mating disruption during the first generation, whereas the opposite was true in blocks treated with insecticides during the first generation. Despite reduced trap catches in pheromone-treated blocks, egg mass densities were not reduced in these blocks compared with insecticide-treated blocks. Furthermore, fruit damage was not significantly different between mating disruption blocks and conventionally treated blocks in orchards with relatively low populations of tufted apple bud moth, but damage was greater in mating disruption blocks in orchards with higher moth densities.     

SPLAT-OrB reveals competitive attraction as a mechanism of mating disruption in oriental beetle (Coleoptera: Scarabaeidae)

This study compared the efficacy of SPLAT-OrB, a new pheromone formulation for oriental beetle mating disruption that can be mechanically applied, with hand-applied plastic dispensers in commercial blueberry fields. Both formulations were tested at 2.5 and 5 g of the major sex pheromone component (Z)-7-tetradecen-2-one per hectare, and evaluated by measuring trap shut-down, mating success of caged females, and the number of grubs in sentinel blueberry pots baited with tethered females. All pheromone-treated plots had fewer male captures in traps and lower mating success of caged females compared with untreated plots. SPLAT-OrB, and plastic dispensers at the higher rate, also reduced the number of grubs in sentinel pots. To understand the mechanism of mating disruption in oriental beetle, males were observed approaching the pheromone sources in disrupted plots. In addition, male oriental beetle captures were quantified in plots treated with varying SPLAT-OrB dollop densities per ha. Consistent with predictions for competitive attraction, field observations revealed males approaching the pheromone source and male captures decreasing concavely with increasing dollop density. In a mark-release-recapture study, male oriental beetles responded to SPLAT-OrB dollops and plastic dispensers at least 60 m from the source. Additionally, SPLAT-OrB emitted pheromone that was attractive to male oriental beetles for >5 wk; however, emission rates and attraction dropped rapidly during the first 3-4 wk. This study demonstrates the feasibility of using SPLAT-OrB for oriental beetle mating disruption as an alternative to hand-applied plastic dispensers, and conclusively reveals that a principal mechanism is the competitive attraction of males.     

Effects of different sex pheromone compositions and host plants on the mating behavior of two Grapholita species

The two congener species Grapholita molesta and Grapholita dimorpha share two major sex pheromone components: cis-8-dodecenyl acetate (Z8-12Ac) and trans-8-dodecenyl acetate (E8-12Ac). In fact, commercial sex pheromone lures composed of only these two major components attract the males of both species. In this study, we aimed to determine the reproductive isolation components of these two species by analyzing the effects of the minor sex pheromone components and host plants. First, different ratios of the two major sex pheromone components were greatly favored by either male species. Sex pheromone gland extracts of G. dimorpha contained a lesser proportion of Z8-12Ac than that of G. molesta. In the three (apple, pear, and peach) orchards investigated in this study, a larger number of G. molesta males were attracted to the 95:5 pheromone mixture (Z8-12Ac and E8-12Ac, respectively), while a larger number of G. dimorpha males were attracted to the 85:15 mixture. Second, there was a significant variation in male attractions in different host plants. G. molesta males were more attracted to the sex pheromone lure in the apple orchards than that in the pear and peach orchards. In contrast, G. dimorpha males were more attracted to the lures in the pear and peach orchards than that in the apple orchard. Third, the minor sex pheromone components were important for reproductive isolation. Among the four minor components tested, addition of (Z)-8-dodecenol (Z8-12OH) to the major sex pheromone components significantly suppressed male attraction in G. dimorpha and slightly elevated male attraction in G. molesta. The discriminating effect of Z8-12OH was further validated using male electroantennogram analysis. These results suggest that reproductive isolation between two congeners can be achieved by variations in the minor sex pheromone components and in the host plants, as well as by changes in the ratio of the two major components.     

Mating disruption barriers in pome fruit for improved control of oriental fruit moth Grapholita molesta Busck (Lep., Tortricidae) in stone fruit under mating disruption

Oriental fruit moth (OFM) Grapholita molesta Busck (Lep., Tortricidae) is a very important pest in commercial orchards in Victoria, Australia. Pheromone‐mediated mating disruption (MD) applied in stone fruit orchards successfully controlled OFM populations for many years, but damage to shoot tips and fruit at the edge of peach blocks located adjacent to pear blocks under insecticide treatments has become problematic. To improve protection of stone fruit against edge damage and outbreaks of OFM, all orchards were treated with sex pheromone dispensers for MD on an area‐wide basis. Area‐wide MD treatment, including all pome and stone fruit orchards in a discrete area, successfully controlled edge infestations of OFM, but was expensive. To reduce the cost of OFM control, sex pheromone dispensers for MD were applied as barrier treatments to 54–60 m of neighbouring pears adjacent to peaches under MD. Detailed monitoring of the OFM population, shoot tip and fruit damage assessments indicated that application of MD barriers on pears during two consecutive seasons provided sufficient control of OFM on peaches. This MD barrier treatment was able to reduce the number of OFM caught in all experimental peach blocks, with damage to shoot tips and fruit giving similar results to MD treatment of the whole neighbouring pear block. Extending the MD treatment area for 54–60 m into the neighbouring pear block significantly reduced the edge damage in MD‐treated peaches in the first season and almost eliminated OFM damage in the second season.     

Application of synthetic sex pheromone for management of diamondback moth, Plutella xylostella, in cabbage

Over a 2-year period field trials were conducted to assess the potential to disrupt mating ofPlutella xylostella (L.) using a commercial rope formulation of a 70:30 mixture of (Z)-11-hexadecenal and (Z)-11-hexadecenyl acetate, two components of the sex pheromone of the female. Screened field cages were placed into blocks of cabbage which were either treated with the pheromone or left untreated. Different densities of P. xylostella pupae were placed into each cage and then larval and pupal counts were made of the subsequent generation. In addition, sentinel females at mating stations were placed in each cage to assess the influence of the pheromone on the ability of males to locate and mate with females. Likewise, we used pheromone traps to assess whether the pheromone treatment influenced the ability of males to locate a pheromone source. In both years larval and pupal populations, produced as a result of the original inoculation, did not differ between pheromone-treated and untreated fields. The effect of pheromone treatment on larval and pupal numbers did not change with changes in inoculated P. xylostella density, however, the density of P. xylostella released caused significant differences in the density of the subsequent generation. No significant differences were detected between the number of sentinel female adult P. xylostella that successfully mated in pheromone-treated fields compared with untreated fields. Significant differences in the numbers of male P. xylostella caught in pheromone-baited traps occurred between pheromone-treated and untreated fields in the first trial of 1993, and in the first trial in 1994 but not in the second trial. Such differences are often thought of as indications of mating disruption, although our other data presented in this study and reports from other studies indicate this is not always the case. Previous studies on mating disruption of P. xylostella in larger scale field tests have been performed but the results have been variable and often ambiguous. Overall, our results indicate that mating disruption of P. xylostella with the present technology does not appear to work even under the very controlled situations which we utilized to eliminate insect movement between plots.     

Suppression of leopard moth (Lepidoptera: Cossidae) populations in olive trees in Egypt through mating disruption

The leopard moth, Zeuzera pyrina (L.) (Lepidoptera: Cossidae), is a damaging pest for many fruit trees (e.g., apple [Malus spp.], pear [Pyrus spp.] peach [Prunus spp.], and olive [Olea]). Recently, it caused serious yield losses in newly established olive orchards in Egypt, including the death of young trees. Chemical and biological control have shown limited efficiency against this pest. Field tests were conducted in 2005 and 2006 to evaluate mating disruption (MD) for the control of the leopard moth, on heavily infested, densely planted olive plots (336 trees per ha). The binary blend of the pheromone components (E,Z)-2,13-octadecenyl acetate and (E,Z)-3,13-octadecenyl acetate (95:5) was dispensed from polyethylene vials. Efficacy was measured considering reduction of catches in pheromone traps, reduction of active galleries of leopard moth per tree and fruit yield in the pheromone-treated plots (MD) compared with control plots (CO). Male captures in MD plots were reduced by 89.3% in 2005 and 82.9% in 2006, during a trapping period of 14 and 13 wk, respectively. Application of MD over two consecutive years progressively reduced the number of active galleries per tree in the third year where no sex pheromone was applied. In all years, larval galleries outnumbered moth captures. Fruit yield from trees where sex pheromone had been applied in 2005 and 2006 increased significantly in 2006 (98.8 +/- 2.9 kg per tree) and 2007 (23 +/- 1.3 kg per tree) compared with control ones (61.0 +/- 3.9 and 10.0 +/- 0.6 kg per tree, respectively). Mating disruption shows promising for suppressing leopard moth infestation in olives.     

Potential for mating disruption to reduce cone damage by the spruce seed moth, Cydia strobilella, in spruce seed orchards

Abstract:  The spruce seed moth, Cydia strobilella (L.), is a serious and widely distributed pest of spruce seed orchards in North America and Europe. Current pest management activities in seed orchards rely mainly on chemical pesticides for insect control. Mating disruption with sex pheromone is a potential alternative pest management tool for C. strobilella . In 2002, field tests confirmed that sticky traps baited with 3  μ g of (E) -8-dodencenyl acetate ( E 8-12:Ac), the sex pheromone of C. strobilella , could capture males in Quebec, a region of Canada not previously monitored for this insect. In the following years (2003–2005), grey rubber septa loaded with 0.75, 1.5, or 2.0 mg of E 8-12:Ac were deployed separately in two white spruce seed orchards at a density of 40 and 60 dispensers/ha to test the potential for mating disruption. The results showed that the captures of male C. strobilella in the pheromone-treated plots were reduced by up to 98%. Furthermore, at the end of the experiment in 2005, 17.3% of cones were damaged by C. strobilella in the treated plot, compared with a significantly (P < 0.0001) higher 56.4% in the control plot. The results suggest that mating disruption has potential for controlling C. strobilella to protect seed cones in white spruce seed orchards.     

Disruption of pheromone communication of Choristoneura rosaceana (Lepidoptera: Tortricidae) using microencapsulated sex pheromones formulated with horticultural oil

Sprayable, microencapsulated (MEC) sex pheromone formulations represent a promising tool for achieving mating disruption, yet often lack sustained effectiveness in the field, making repeated applications necessary. This study evaluated the impact of adding Purespray Green horticultural oil as an adjuvant to 3M MEC-LR, an MEC formulation of (Z)-11-tetradecenyl acetate, on disruption of mate-finding behavior in Choristoneura rosaceana (Harris) in small-plot trials in experimental apple orchards. Treatments consisting of MEC-LR in water, MEC-LR in water + 2% (vol:vol) Purespray Green, and a water control were applied to plots of apple using an airblast sprayer at a rate of 100 g of pheromone/ha. Disruption caused by foliar treatments was evaluated over a 7-wk period using mark-release recapture experiments in the field and concurrent bioassays in a flight tunnel. Disruption of orientation to 2-d-old, calling, virgin females was used as a measure of treatment effect in all experiments. Both pheromone alone and pheromone + oil treatments significantly disrupted male mate-finding behavior for a period of > or =21 d in flight tunnel assays and > or =42 d in mark-recapture field trials. The addition of oil did not significantly enhance the disruption activity nor increase the longevity of the MEC pheromone formulation. Our results show the compatibility of spraying MEC pheromone with a horticultural oil, and techniques for applying an oil-pheromone formulation to maximize the control impact of this combination are discussed.     

Sprayable microencapsulated sex pheromone formulation for mating disruption of oriental fruit moth (Lepidoptera: Tortricidae) in Australian peach and pear orchards

Areawide mating disruption treatments have been effective in controlling infestation of oriental fruit moth, Grapholita molesta (Busck) (Lepidoptera: Tortricidae), in Australian pome and stone fruit orchards. Although successful, the areawide mating disruption program has been an expensive approach by using hand-applied Isomate dispensers. Sprayable microencapsulated (MEC) pheromone formulations that can be applied with standard spray equipment could substantially reduce the cost of application. Field trials conducted during two consecutive seasons (2002-2004) demonstrated that monthly applications of MEC-OFM phase V (3M Canada, London, Ontario, Canada) at a rate of 125 ml/ha (37.1 g [AI]/ha) in replicated 2-ha blocks of both peaches and pears reduced oriental fruit moth shoot tip and fruit damage as effectively as a single application of Isomate OFM Rosso hand-applied dispensers (500 dispensers per ha) and as or more effectively than standard broad-spectrum insecticide sprays. Fruit protection was achieved despite high oriental fruit moth population densities in both crops as measured by moth catches in terpinyl acetate food and pheromone traps. Similar numbers of oriental fruit moths were captured among all treatments in food traps but captures of males in pheromone traps were disrupted (96-99%) in pheromone-treated blocks relative to controls. The results of this study suggest that microencapsulated formulations of pheromone could be effectively used in areawide mating disruption programs for oriental fruit moth in Australia as a cost-saving alternative to reservoir-style dispensers requiring labor-intensive hand application.