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Male Cydia pomonella (L.) (Lepidoptera: Tortricidae) dispersion has largely been studied in nonmating disrupted orchards due to synthetic pheromone interference with capture in monitoring traps. Little is known about female dispersion. This study aimed to characterize male and female dispersion in mating disrupted commercial apple orchards. Sterile C. pomonella recapture data from single-trap multiple-release experiments using PHEROCON CM-DA COMBO + AA Lure-baited orange Pherocon VI delta traps was interpreted to determine pheromone-kairomone lure-baited trap effective area, trap deployment density for effective monitoring, and absolute male and female C. pomonella density in mating disrupted Washington commercial apple orchards. The maximum plume reach of the pheromone-kairomone lure in mating disrupted orchards was <5 m from the baited trap for both sexes. Maximum dispersive distances for 95% of the released C. pomonella in mating disrupted orchards were 106 and 135 m for males and females, yielding trapping areas of 3.87 and 6.16 ha, respectively. Estimates were consistent across 3 growing seasons and represent the first records of male and female dispersal distance and monitoring trap efficacy from commercial C. pomonella mating disrupted apple orchards. With relevance to commercial monitoring programs and economic thresholds in mating disrupted orchards, traps should be deployed at a density of 1 per 3-6 ha. Capture of a single male or female C. pomonella corresponds to at least 82-104 C. pomonella within the 3-6 ha trapping area. This refined C. pomonella capture interpretation in pheromone-kairomone baited traps in mating disrupted commercial apple orchards yields more precise damage estimates and assists in insecticide-use decision making., (© The Author(s) 2023. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Fungicides are commonly applied to prevent diseases in eastern North American cherry orchards at the same time that honey bees (Apis mellifera L. (Hymenoptera: Apidae)) are rented for pollination services. Fungicide exposure in honey bees can cause negative health effects. To measure fungicide exposure, we sampled commercial honey bee colonies during orchard bloom at two commercial tart cherry orchards and one holding yard in northern Michigan over two seasons. Nurse bees, foragers, larvae, pollen, bee bread, and wax were screened for captan, chlorothalonil, and thiophanate-methyl. We also looked at the composition of pollens collected by foragers during spring bloom. We found differences in fungicide residue levels between nurse bees and foragers, with higher captan levels in nurse bees. We also found that residue levels of chlorothalonil in workers were significantly increased during tart cherry bloom, and that nurse bees from hives adjacent to orchards had significantly higher chlorothalonil residues than nurse bees from hives kept in a holding yard. Our results suggest that fungicide exposure of individual honey bees depends greatly on hive location in relation to mass-flowering crops, and worker role (life stage) at the time of collection. In some pollen samples, captan and chlorothalonil were detected at levels known to cause negative health effects for honey bees. This study increases our understanding of exposure risk for bees under current bloom time orchard management in this region. Further research is needed to balance crop disease management requirements with necessary pollination services and long-term pollinator health., (© The Author(s) 2023. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Background: Invasive species threaten the productivity and stability of natural and managed ecosystems. Predicting the spread of invaders, which can aid in early mitigation efforts, is a major challenge, especially in the face of climate change. While ecological niche models are effective tools to assess habitat suitability for invaders, such models have rarely been created for invasive pest species with rapidly expanding ranges. Here, we leveraged a national monitoring effort from 543 sites over 3 years to assess factors mediating the occurrence and abundance of brown marmorated stink bug (BMSB, Halyomorpha halys), an invasive insect pest that has readily established throughout much of the United States., Results: We used maximum entropy models to estimate the suitable habitat of BMSB under several climate scenarios, and generalized boosted models to assess environmental factors that regulated BMSB abundance. Our models captured BMSB distribution and abundance with high accuracy, and predicted a 70% increase in suitable habitat under future climate scenarios. However, environmental factors that mediated the geographical distribution of BMSB were different from those driving abundance. While BMSB occurrence was most affected by winter precipitation and proximity to populated areas, BMSB abundance was influenced most strongly by evapotranspiration and solar photoperiod., Conclusion: Our results suggest that linking models of establishment (occurrence) and population dynamics (abundance) offers a more effective way to forecast the spread and impact of BMSB and other invasive species than simply occurrence-based models, allowing for targeted mitigation efforts. Implications of distribution shifts under climate change are discussed. © 2022 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry., (© 2022 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.)

Drosophila suzukii (Matsumura, 1931) (Diptera: Drosophilidae) is a vinegar fly native to East Asia that has rapidly expanded its range to become a pest of sweet cherry (Prunus avium, L. 1753 [Rosales: Rosaceae]) and tart cherry (P. cerasus, L. 1753) in North America and Europe. The goal of the research presented herein was to improve the decision-making process for managing D. suzukii in tart cherry. Knowing that D. suzukii females are attracted to ripening fruit, we measured fruit infestation by D. suzukii as it relates to an existing fruit development model that uses full bloom as a biofix, calculating accumulated growing degree days (GDD) with a lower threshold of 4°C. Increasing larval infestation was highly correlated with fruit development expressed as GDD post-bloom with very few larvae developing in fruit subjected to no-choice assays prior to 530 GDD (base 4°C) and no larvae detected in naturally infested fruit prior to 800 GDD. Our findings provide the first quantification of the relationship between fruit development and D. suzukii infestation that allows for pinpointing the timing of fruit susceptibility and that could be used as the basis for a more sustainable management program for this pest in tart cherry orchards., (© The Author(s) 2022. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Background odors produced by plants in the environment can interfere with the response of insects to a point-releasing attractant, especially when their compositions overlap. In this study, a series of binary choice tests was conducted in a wind tunnel to investigate whether background odors emitted from cherry, blueberry, blackberry, or raspberry fruits would affect the level of Drosophila suzukii (Matsumura) attraction to its symbiotic yeast, Hanseniaspora uvarum (Niehaus) (Saccharomycetales: Saccharomycetaceae). Whether an increase in the intensity of background odors would affect the attractiveness of H. uvarum to D. suzukii was also investigated, either by increasing the number of cherry or raspberry fruit per cup or by increasing the number of fruit cups surrounding the cup baited with the yeast. In wind tunnel assays, background fruit odors interfering with D. suzukii attraction to the yeast varied among fruit types. Raspberry odor inhibited the attractiveness of H. uvarum to the fly the most, followed by blackberry odor, whereas cherry and blueberry odors had no significant impact on the attraction. An increase in the intensity of odors by adding more cherry or raspberry fruit per cup did not increase the impact of fruit odor on the attraction; however, adding more raspberry cups around H. uvarum linearly decreased its attractiveness, suggesting that background host fruit abundance and likely increase in host odor may influence D. suzukii attraction to yeast odor depending on host species., (© The Author(s) 2021. Published by Oxford University Press on behalf of Entomological Society of America.)

Reliable monitoring of the invasive Halyomorpha halys abundance, phenology and geographic distribution is critical for its management. Halyomorpha halys adult and nymphal captures on clear sticky traps and in black pyramid traps were compared in 18 states across the Great Lakes, Mid-Atlantic, Southeast, Pacific Northwest and Western regions of the United States. Traps were baited with commercial lures containing the H. halys pheromone and synergist, and deployed at field sites bordering agricultural or urban locations with H. halys host plants. Nymphal and adult captures in pyramid traps were greater than those on sticky traps, but captures were positively correlated between the two trap types within each region and during the early-, mid- and late season across all sites. Sites were further classified as having a low, moderate or high relative H. halys density and again showed positive correlations between captures for the two trap types for nymphs and adults. Among regions, the greatest adult captures were recorded in the Southeast and Mid-Atlantic on pyramid and sticky traps, respectively, with lowest captures recorded in the West. Nymphal captures, while lower than adult captures, were greatest in the Southeast and lowest in the West. Nymphal and adult captures were, generally, greatest during July-August and September-October, respectively. Trapping data were compared with available phenological models showing comparable population peaks at most locations. Results demonstrated that sticky traps offer a simpler alternative to pyramid traps, but both can be reliable tools to monitor H. halys in different geographical locations with varying population densities throughout the season., (© The Author(s) 2019. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

The invasive spotted-wing drosophila, Drosophila suzukii (Matsumura), is a major pest of soft-skinned fruits. Since its introduction into North America and Europe, significant progress has been made in understanding the volatile cues used by this fly during food, oviposition site, and mate finding. Despite this progress, commercially available lures are non-selective. Here, we tested two Hanseniaspora uvarum (Niehaus) yeast compounds (isoamyl acetate and isobutyl acetate) and a leaf compound β-cyclocitral alone and in combination with a blend of four fermentation compounds ('Fermentation lure': acetic acid, ethanol, methionol, and acetoin) to improve D. suzukii attraction and selectivity. In laboratory assays, males and females were attracted to all seven individual compounds, although in electrophysiological assays, their antennae exhibited a dose-dependent response to only four of these compounds. In two-choice cage studies, the Fermentation lure was more attractive to D. suzukii than water controls, whereas β-cyclocitral and the mixture of isoamyl acetate and isobutyl acetate were not attractive in this larger-cage study. Moreover, adding the two-component H. uvarum compound blend to the Fermentation lure reduced D. suzukii attraction to the Fermentation blend. When these experiments were repeated in blueberry, raspberry, blackberry, and cherry orchards across several states in the United States over 2 yr, similar outcomes were observed: β-cyclocitral or the mixture of the H. uvarum blend did not improve the attractiveness of the Fermentation lure or its selectivity. This study demonstrates that cues from different sources may interfere with each other and reduce D. suzukii attraction to otherwise attractive odor combinations., (© The Author(s) 2019. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Halyomorpha halys (Stål) (Hemiptera: Pentatomidae), the brown marmorated stink bug, is an invasive polyphagous insect that can cause serious economic injury to specialty and row crops in the United States and globally. To date, H. halys has been managed with repeated insecticide applications. While progress has been made toward development of trap-based monitoring tools to guide management decisions, little is known regarding the trapping area over which a single pheromone-baited trap captures H. halys. We conducted single trap, multiple distance mark-release-recapture experiments; results were used to estimate trapping area for nymphs and adults in sites without host plants present (open field) and for adults in sites with host plants present (apple orchard). Plume reach for pheromone-baited sticky traps was consistently estimated to be <3 m. Maximum dispersive distance in an open field devoid of host plants was estimated to be 40 m for nymphs and 120-130 m for adults resulting in trapping areas of 0.58 ha and 4.83-5.56 ha, respectively. When traps were deployed in association with host plants within the border row of an apple orchard, adult maximum dispersive distance and trapping area was reduced to 70 m and 1.67 ha, respectively. These results indicate that the behavioral response of H. halys to pheromonal stimuli is influenced by the presence of host plants and that trapping area for pheromone-baited traps will likely change relative to the cropping system in which it is deployed. Caution should be taken when extrapolating these results, because the measured values may differ in other crop systems., (Published by Oxford University Press on behalf of Entomological Society of America 2019.)

Field populations of Obliquebanded leafroller, Choristoneura rosaceana (Harris), collected from one commercial apple and one commercial cherry orchard in Kent and Newaygo Counties in western Michigan, respectively. A baseline toxicity study of eight insecticides including phosmet, bifenthrin, methomyl, indoxacarb, chlorantraniliprole, spinetoram, emamectin benzoate, and novaluron was conducted on 12- to 24-h-old larvae of the C. rosaceana field populations and compared with a susceptible strain. The resistance levels were low (<10-fold) in all cases except for indoxacarb (>10-fold) in both populations. The cherry population showed levels of resistance to spinetoram, bifenthrin, emamectin benzoate, and indoxacarb with 4.1-, 4.9-, 5.8-, and 21-fold resistance, respectively. The apple population showed levels of resistance to spinetoram, chlorantraniliprole, phosmet, bifenthrin, emamectin benzoate, and indoxacarb with 4.3-, 4.7-, 5-, 5-, 6.3-, and 620.4-fold resistance, respectively. Generally, the apple population showed lower resistance levels to more compounds than the cherry population. Resistance to these insecticides should be monitored periodically for further changes. This represents the first documented case of insecticide resistance for C. rosaceana collected from a cherry orchard in Michigan. A statewide survey of more commercial orchards would help determine the extent of insecticide resistance across Michigan's five tree fruit production regions., (© The Author(s) 2018. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Drosophila suzukii Matsumura (Diptera: Drosophilidae) is currently one of the most serious invasive pests for berry crops and cherries worldwide. The development of an effective monitoring trap that is reliable at detecting small populations to guide management decisions is greatly needed. To develop a novel dry trapping system, D. suzukii were trapped under field conditions in cherry orchards and raspberry high tunnels using various baited dry trap designs that were compared with the currently available deli-cup style traps that utilize a liquid bait or drowning solution. In a test in cherry orchards, red panel and combination yellow panel plus red sphere traps captured significantly more flies than yellow panel traps when all were baited with a Scentry lure. In a separate test in cherry, red sphere traps with the Scentry lure captured significantly more flies than the deli-cup traps with the Scentry lure or with the yeast sugar bait, and red panel traps with the Scentry lure captured significantly more flies than deli-cup traps with the Scentry lure. In raspberry high tunnels, red sphere traps with the Scentry lure captured significantly more flies than deli-cup traps with the Scentry lure. Red traps baited with the same lure as clear deli-cup traps consistently captured more D. suzukii, demonstrating that traps integrating a visual cue in combination with an olfactory cue are superior tools for monitoring D. suzukii. A dry trap requires less labor and maintenance than cup traps containing a liquid, improving the ease of use of D. suzukii monitoring traps., (© The Author(s) 2018. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Declines in the number of commercial honey bees (Apis mellifera L.) (Hymenoptera: Apidae) and some wild bee species around the world threaten fruit, nut, and vegetable production and have prompted interest in developing methods for gaining efficiencies in pollination services. One possible approach would be to deploy attractants within the target crop to increase the number of floral visits. In this study, we evaluate two new pollinator attractants, Polynate and SPLAT Bloom, for their ability to increase pollinator visitation and fruit set in apple (Malus pumila Mill.), highbush blueberry (Vaccinium sp. L.), and tart cherry (Prunus cerasus L.). Polynate is a plastic twin-tube dispenser loaded with a mixture of floral scent and Nasonov pheromone. SPLAT Bloom contains the same chemical formula as Polynate, but is applied as a 3 g wax dollop directly onto the tree or bush. The objectives of this study were to determine if Polynate and SPLAT Bloom increase the number of honey bee foragers and fruit set in apples, highbush blueberries, and tart cherries. We conducted replicated evaluations of 32 fields or orchards with and without putative attractants over three growing seasons. Both products failed to provide a measurable increase in pollinator visits or fruit set in these crops, indicating no return on investment for either product., (© The Author(s) 2018. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Drosophila suzukii (Matsumura) (Diptera: Drosophilidae) is a devastating global pest of berry crops and cherries. Little is understood about its biology during the winter in northern temperate regions, including potential resources that it may utilize during this period. In this study, olfactory and behavioral responses of female D. suzukii to six volatiles (methionol, acetic acid, linalool, bornyl acetate, isoamyl acetate, and geosmin) were evaluated separately for electroantennogram (EAG) and behavioral assays between summer and winter morphs. Results of EAG indicated that isoamyl acetate, acetic acid, and geosmin elicited significantly higher olfactory responses from the antennae of female summer morph D. suzukii compared with those of female winter morph D. suzukii. Winter morph D. suzukii showed reduced antennal response to the volatiles overall. Geosmin and bornyl acetate elicited significantly different behavioral responses from the two morphs in no-choice laboratory behavioral assays. T-maze behavioral assays with geosmin further revealed that summer morphs had a significant aversion, while winter morphs showed no significant aversion to geosmin. Overall, we demonstrate that responses of the two seasonally induced morphs to environmental stimuli are different, and future studies are justified to further understand how these physiological and behavioral differences may contribute to improved pest management of D. suzukii.

Central-monitoring trap, multiple point release-recapture experiments were used to interpret Drosophila suzukii (Diptera: Drosophilidae) catch in a monitoring trap baited with a Scentry Biologicals commercial D. suzukii lure deployed in Michigan tart cherry orchards. The plume reach was found to be short (<3 m), while the maximum dispersive distance for 95% of the released D. suzukii was projected to be ca. 90 m, so as to yield a trapping area of 2.7 ha. These data were consistent across two growing seasons and provide the first information about the dispersal distance and monitoring trap efficacy in a fruit crop setting for D. suzukii. Catch data per single monitoring trap can now be used to estimate absolute pest density in cherries. Alarmingly, catching one D. suzukii in a monitoring trap translates to approximately 192 D. suzukii per trapping area of 2.7 ha (26 per acre). Thus, by the time D. suzukii catch becomes detectable, it is very probable that the population is already above the tolerable damage threshold, suggesting control measures should immediately be taken if the fruit is in a vulnerable stage. Caution should be taken when extrapolating these results from cherry because the measured values may differ in other crop systems.

This field study of codling moth, Cydia pomonella (L.), response to single versus multiple monitoring traps baited with codlemone demonstrates that precision of a given capture number is alarmingly poor when the population is held constant by releasing moths. Captures as low as zero and as high as 12 males per single trap are to be expected where the catch mode is three. Here, we demonstrate that the frequency of false negatives and overestimated positives for codling moth trapping can be substantially reduced by employing the tactic of line-trapping, where five traps were deployed 4 m apart along a row of apple trees. Codling moth traps spaced closely competed only slightly. Therefore, deploying five traps closely in a line is a sampling technique nearly as good as deploying five traps spaced widely. But line trapping offers a substantial savings in time and therefore cost when servicing aggregated versus distributed traps. As the science of pest management matures by mastering the ability to translate capture numbers into estimates of absolute pest density, it will be important to employ a tactic like line-trapping so as to shrink the troublesome variability associated with capture numbers in single traps that thwarts accurate decisions about if and when to spray. Line-trapping might similarly increase the reliability and utility of density estimates derived from capture numbers in monitoring traps for various pest and beneficial insects., (© The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America.)

Novel methods of data analysis were used to interpret codling moth (Cydia pomonella) catch data from central-trap, multiple-release experiments using a standard codlemone-baited monitoring trap in commercial apple orchards not under mating disruption. The main objectives were to determine consistency and reliability for measures of: 1) the trapping radius, composed of the trap's behaviorally effective plume reach and the maximum dispersive distance of a responder population; and 2) the proportion of the population present in the trapping area that is caught. Two moth release designs were used: 1) moth releases at regular intervals in the four cardinal directions, and 2) evenly distributed moth releases across entire approximately 18-ha orchard blocks using both high and low codling moth populations. For both release designs, at high populations, the mean proportion catch was 0.01, and for the even release of low populations, that value was approximately 0.02. Mean maximum dispersive distance for released codling moth males was approximately 260 m. Behaviorally effective plume reach for the standard codling moth trap was < 5 m, and total trapping area for a single trap was approximately 21 ha. These estimates were consistent across three growing seasons and are supported by extraordinarily high replication for this type of field experiment. Knowing the trapping area and mean proportion caught, catch number per single monitoring trap can be translated into absolute pest density using the equation: males per trapping area = catch per trapping area/proportion caught. Thus, catches of 1, 3, 10, and 30 codling moth males per trap translate to approximately 5, 14, 48, and 143 males/ha, respectively, and reflect equal densities of females, because the codling moth sex ratio is 1:1. Combined with life-table data on codling moth fecundity and mortality, along with data on crop yield per trapping area, this fundamental knowledge of how to interpret catch numbers will enable pest managers to make considerably more precise projections of damage and therefore more precise and reliable decisions on whether insecticide applications are justified. The principles and methods established here for estimating absolute codling moth density may be broadly applicable to pests generally and thereby could set a new standard for integrated pest management decisions based on trapping., (© The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America.)

Experiments were conducted in commercial apple orchards to determine if improved efficiencies in pheromone delivery may be realized by using aerosol pheromone dispensers for codling moth (CM), Cydia pomonella L., mating disruption. Specifically, we tested how reducing: pheromone concentration, period of dispenser operation, and frequency of pheromone emission from aerosol dispensers affected orientational disruption of male CM to pheromone-baited monitoring traps. Isomate® CM MIST formulated with 50 % less codlemone (3.5 mg/ emission) provided orientation disruption equal to the standard commercial formulation (7 mg / emission). Decreased periods of dispenser operation (3 and 6 h) and frequency of pheromone emission (30 and 60 min) provided a level of orientational disruption similar to the current standard protocol of releasing pheromone over a 12 h period on a 15 min cycle, respectively. These three modifications provide a means of substantially reducing the amount of pheromone necessary for CM disruption. The savings accompanying pheromone conservation could lead to increased adoption of CM mating disruption and, moreover, provide an opportunity for achieving higher levels of disruption by increasing dispenser densities.

Methods for trapping spotted wing drosophila, Drosophila suzukii (Matsmura) (Diptera: Drosophilidae), have not yet been optimized for detecting this devastating pest of soft-skinned fruits. Here, we report outcomes of choice and no-choice laboratory bioassays quantifying the rates of spotted wing drosophila alightment on 5-cm-diameter sticky disks of various colors, but no fruit odors. Red, purple, and black disks captured the most spotted wing drosophila when presented against a white background. Male and female spotted wing drosophila responded identically in these tests. Significantly more D. suzukii were captured on the red and yellow disks than those presenting the corresponding grayscale for that color, proving that D. suzukii perceives colors and not just the level of target brightness. Fluorescent red is the best candidate for trap color, while clear and white are the least desirable. However, when the background was switched to black, all nonfluorescent colors were equally acceptable to spotted wing drosophila, suggesting that background must be specified when reporting spotted wing drosophila color preference. Additional spotted wing drosophila research is justified on the effects of target color against natural backgrounds., (© The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America.)

Progress toward proof of the principal cause of insect mating disruption under a particular set of conditions has been hindered by a lack of logical rigor and clean falsifications of possible explanations. Here we make the case that understanding of mating disruption and optimization of particular formulations can be significantly advanced by rigorous application of the principles of strong inference. To that end, we offer a dichotomous key for eight distinct categories of mating disruption and detail criteria and methodologies for differentiating among them. Mechanisms of mating disruption closely align with those established for enzyme inhibition, falling into two major categories-competitive and noncompetitive. Under competitive disruption, no impairments are experienced by males, females, or the signal of females. Therefore, males can respond to females and traps. Competitive disruption is entirely a numbers game where the ratio of dispensers to females and traps is highly consequential and renders the control pest-density-dependent. Under noncompetitive disruption, males, females, or the signal from females are already impaired when sexual activity commences. The control achieved noncompetitively offers the notable advantage of being pest-density-independent. Dosage-response curves are the best way to distinguish competitive from noncompetitive disruption. Purely competitive disruption produces: a smoothly concave curve when untransformed capture data are plotted on the y-axis against density of dispensers on the x-axis; a straight line with positive slope when the inverse of catch is plotted against density of pheromone dispensers; and, a straight line with negative slope when catch is plotted against density of pheromone dispensers × catch. Disruption operating only noncompetitively produces: a straight line with negative slope when untransformed capture data are plotted on the y-axis against density of dispensers on the x-axis; an upturning curve when the inverse of catch is plotted against density of pheromone dispensers; and, a recurving plot when catch is plotted against density of pheromone dispensers x catch. Hybrid profiles are possible when some males within the population begin the activity period already incapacitated, while those not preexposed have the capacity to respond either to traps or pheromone dispensers. Competitive mechanisms include competitive attraction, induced allopatry, and induced arrestment. Noncompetitive mechanisms include desensitization and inhibition, induced allochrony, suppressed calling and mating, camouflage, and sensory imbalance. Examples of the various disruption types within the two major categories and suggested tactics for differentiating among them are offered as seven case studies of the disruption of important pest species using various formulations are analyzed in depth. We point out how economic optimizations may be achieved once the principal and contributory causes of disruption are proven. Hopefully, these insights will pave the way to a broader and more reliable usage of this environmentally friendly pest management tactic., (© The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

Background: Isomate(®) CM MIST aerosol emitters (Pacific BioControl Corp, Vancouver, WA) containing 36 g of codlemone, (E,E)-8,10-dodecadien-1-ol, were deployed at various densities in a commercial apple orchard to generate dosage-response profiles in order to elucidate the behavioral mechanism of disruption., Results: Moth captures decreased asymptotically as Isomate(®) CM MIST densities increased. Data fitting to Miller-Gut and Miller-de Lame plots yielded straight lines, with positive and negative slopes respectively. Catch of male moths decreased from 28 trap(-1) in the control to 0.9 trap(-1) at the highest emitter density. Disruption of >90% was realized at emitter densities greater than 5 units ha(-1) ., Conclusion: The resulting set of profiles explicitly matched the predictions for competitive rather than non-competitive disruption. Thus, these devices probably disrupt by inducing false-plume following rather than by camouflaging traps and females. The use of 5 MIST units ha(-1) would be necessary to achieve the same level of codling moth control provided by a standard pheromone treatment with passive reservoir dispensers. The need for only a few aerosol emitters, 2.5-5 units ha(-1) , mitigates the cost of labor required to hand-apply hundreds of passive reservoir dispensers; however, a potential weakness in using this technology is that the low deployment density may leave areas of little or no pheromone coverage, where mate finding may occur. This technology is likely to benefit substantially from treatment of large contiguous blocks of crop., (© 2014 Society of Chemical Industry.)

Drosophila suzukii (Matsumura), an invasive pest of small and stone fruits, has been recently detected in 39 states of the United States, Canada, Mexico, and Europe. This pest attacks ripening fruit, causing economic losses including increased management costs and crop rejection. Ongoing research aims to improve the efficacy of monitoring traps. Studies were conducted to evaluate how physical trap features affect captures of D. suzukii. We evaluated five colors, two bait surface areas, and a top and side position for the fly entry point. Studies were conducted at 16 sites spanning seven states and provinces of North America and nine crop types. Apple cider vinegar was the standard bait in all trap types. In the overall analysis, yellow-colored traps caught significantly more flies than clear, white, and black traps; and red traps caught more than clear traps. Results by color may be influenced by crop type. Overall, the trap with a greater bait surface area caught slightly more D. suzukii than the trap with smaller area (90 vs. 40 cm(2)). Overall, the two traps with a side-mesh entry, with or without a protective rain tent, caught more D. suzukii than the trap with a top-mesh entry and tent.

The behavior of codling moth, Cydia pomonella (L.), responding to three attract-and-kill devices was compared in flight tunnel experiments measuring attraction and duration of target contact. Placing a 7.6 by 12.6 cm card immediately upwind of a rubber septum releasing pheromone, dramatically increased the duration on the target to > 60 s. In this setting, nearly all the males flew upwind, landed on the card first, and spent the majority of time searching the card. In contrast, male codling moths spent < 15 s at the source if given the lure only. In a forced contact bioassay, knockdown rate or mortality of male codling moths increased in direct proportion to duration of contact on a lambda-cyhalothrin-loaded filter paper. When this insecticide-treated paper was placed immediately upwind of the lure in the flight tunnel, > 90% of males contacting the paper were knocked down 2 h after voluntary exposure. These findings suggest that past attempts to combine insecticide directly with sex pheromones into a small paste, gel, or other forms of dollops are ill-advised because moths are likely over-exposed to pheromone and vacate the target before obtaining a lethal dose of insecticide. It is better to minimize direct contact with the concentrated pheromone while enticing males to extensively search insecticide-treated surface nearby the lure.

Pheromone-based mating disruption is used worldwide for management of the internal fruit feeding codling moth, Cydia pomonella (L.). There has been recent interest in the potential of improving mating disruption of C. pomonella, and potentially other insect species in general, by broadcasting combinations of pheromone and attractive host-plant kairomones. Given that such kairomones are attractive by themselves (often to both sexes), and also enhance male moth response to their pheromone, it is possible that the effects of competitive attraction and potentially other mechanisms of disruption might be increased. Herein, we tested the hypothesis that mating disruption of C. pomonella could be enhanced by co-deploying pheromone with either of two kairomones: (2E, 4Z)-2, 4-decadienoate (pear ester), or (E)-β-farnesene, as compared with various pheromone blend components alone. When deployed individually, each kairomone caused a low level of synthetic lure trap disruption and (E)-β-farnesene also caused disruption of mating as measured by tethering virgin females. However, combined release of either pear ester or (E)-β-farnesene with pheromone within the same dispenser or as a co-deployed dispenser treatment, respectively, did not increase the level of mating disruption as compared with deploying pheromone alone. Disruption efficacy did not decline when reducing the amount of (E,E)-8,10-dodecadien-1-ol (codlemone) in dispensers by fourfold, when combined with pear ester. C. pomonella readily were observed briefly approaching all dispenser types (with and without pheromone) in the field. Exposure of male C. pomonella to pear ester alone in a manner mimicking observed field exposures did not reduce the number of males able to contact a female-mimic pheromone lure in flight tunnel assays. Also, reduction of male moth behavioral response to pheromone was similar after exposure to codlemone alone, and codlemone and pear ester after exposures that mimicked those observed in the field and none of the main treatments tested (pheromone versus pheromone and either kairomone) affected male moth antennal response seconds after exposure as measured by electroantenogram assays. Collectively, our data indicate that disruption of C. pomonella was not improved by co-releasing pheromone with either kairomone tested from point source devices as compared with pheromone alone at the relatively high loading dosages and associated release rates tested.

Background: The effect of varying the height of reservoir dispensers for mating disruption of codling moth, Cydia pomonella (L.), was investigated. The goal was to improve the effectiveness of C. pomonella mating disruption through improved understanding of adult distribution within the tree canopy and the impact of pheromone dispenser placement on disruption. Two dispensers per tree were placed at 2 m and 4 m and/or one dispenser at each height on the tree at a label rate of 1000 units ha(-1) . Monitoring traps and tethered female moths were deployed in plots at 2 and 4 m heights to assess treatment effects by catches or matings respectively., Results: Fewest male moths were captured with all dispensers placed at 4 m. Female mating was lowest, and with least variation between females tethered at 2 and 4 m, when dispensers were placed simultaneously at 2 and 4 m (28% mated). Mating was 32% with both dispensers at 4 m, 38% with both dispensers at 2 m and 46% in the no disruption control. Mating was highest across treatments when females were tethered at 2 m and dispensers placed at 4 m (40%), and when females were tethered at 4 m with dispensers placed at 2 m (46%)., Conclusion: Traps at 4 m in trees captured more male moths than traps at 2 m, regardless of disruption dispenser positioning. Female mating was lowest when dispensers were placed simultaneously at 2 and 4 m, suggesting that current recommendations for placement of reservoir dispensers in tree crowns may be suboptimal., (Copyright © 2011 Society of Chemical Industry.)

Field investigations were conducted to determine the resting locations of codling moth (Cydia pomonella [L.]) (Lepidoptera: Tortricidae) males and females in mating disrupted and nondisrupted apple (Malus domestica Borkh.) orchard plots. A custom-made sampling device, consisting of a leaf blower converted into a powerful vacuum, yielded 20-24% success in recovering marked moths, released in the tree canopy in orchards. Four collections each were made between 0900 and 1800 hours and 1800 and 2200 hours in 2005. Ninety-four moths were collected during the 1800-2200 hours samples. In mating disruption plots, 42% of females and 22% of males were found in the top third of the tree canopy (3.0-4.5m), 46% females and 43% males in the middle third (1.5-3.0m), and 12% female and 35% male in the lower third (0-1.5m). In nondisrupted plots 36.4% of females and 40% of males were in the top third of the canopy, 36.4% females and 52% males in the middle third, and 27.2% females and 8% males in the lower third of the tree canopy. Daylight vacuum sampling recovered only one female and two male moths from the top, four males from the middle and one male from the lower third of the tree canopy. Release-recapture studies of marked adult codling moths were conducted in 2006-2007 in screened tents to determine within orchard habitats for adult moths during 0900-1800 hours. Of moths recaptured, 14.6% of females and 13.5% of males were from the ground (herbicide strip and drive-row grass) and 32.9% of females and 24.6% of males were captured in the tree canopy 16-h post release, 17.4% of females and 3.4% of males from the ground and 26.5% of females and 38.2% of males in the tree 40-h post release, and 15.1% of females and 18.6% of males from the ground and 15.7 of females and 25.5% of males in the tree 64-h post release. Application of pyrethrum + PBO by using an orchard blast sprayer in 2007 resulted in the recapture of 28% and 37% of laboratory reared male and female moths, respectively, from trees during 0900-1800 h. Our results suggest that distributing pheromone dispensers throughout the tree canopy may be more effective than placing them in one location, such as near the tree crown.

Entostat is an electrostatically charged wax powder that can adhere strongly to insect cuticle, making it an ideal carrier to deliver pheromone for pheromone-based confusion techniques. We investigated the attractiveness of Cydia pomonella (L.) (Lepidoptera: Tortricidae) males treated with pheromone-laden Entostat powder to naive conspecifics as well as mating behaviors of males after such treatment in a laboratory flight tunnel. Male moths exposed to Entostat containing 1% E,E-8,10-dodecadien-1-ol (codlemone) acquired and retained the largest amount of the powder and became more attractive as point sources to naive moths compared with those treated with powder containing 5 or 10% codlemone. All Entostat-exposed males remained as attractive as a 0.1-mg codlemone lure for up to 24 h in flight tunnel investigations. Male moth orientation to normally attractive sources of codlemone was completely disrupted directly after treatment with Entostat powder. Males' ability to orient to 0.1-mg lures recovered progressively over a 6-d postexposure interval; however, their responses never reached the levels observed with untreated control moths. Entostat-exposed moths retained detectable amounts of codlemone up to 4 d. Our laboratory flight tunnel results suggest that the mode of action of Entostat powder as an autodissemination control tactic may be due to creating both attractive false point sources after exposure to the powder as well as directly inhibiting contaminated males' capability to orient to pheromone.

The timing and duration of approaches by male peachtree borer Synanthedon exitiosa Say (Lepidoptera: Sesiidae) to commercial pheromone dispensers placed singly or at high density in peach orchards was determined by using field-deployed video cameras and digital video recorders. Cameras were trained on one dispenser, and one standard lure was placed in a peach orchard, and on 12 dispensers in a separate orchard where dispensers for mating disruption had been placed at 371 per hectare. Male moth approaches were video recorded at the peak of peachtree borer annual flight, from 13 to 18 August 2009. The mean approach timing (h:min:sec±SD) during the study period was 11:33:12 ± 00:46:43, 11:43:52 ± 00:45:58, and 11:41:21 ± 00:45:54 AM with the single dispenser, high-density dispensers, and lure, respectively. Day-to-day variability in approach timings suggested that there were no biologically significant differences among treatments. The frequency distribution of approach durations varied among treatments, as the high-density dispensers had mostly short approaches, while the distribution of approaches to the single dispenser and lure was wider. The median (interquartile range) approach duration was 3 (2-4), 1 (1-2), and 4 (2-6) seconds with the single dispenser, high-density dispensers, and lure, respectively. The relative rank of median approach durations was constant throughout the period, indicating differences among treatments. This study showed that the presence of pheromone dispensers for mating disruption did not cause an advancement of peachtree borer diel rhythm of response. Shorter approaches to dispensers placed at high density than singly suggest that dispenser retentiveness is not constant with peachtree borer, which may bias estimates of disruption activity as a function of dispenser density.

Hand-applied dispensers are successfully used in mating disruption programs, but cost of labor to apply these dispensers limits their adoption. Creating hand-applied dispensers that release larger amounts of pheromone and that can be applied at lower densities per hectare could reduce the cost of mating disruption and increase its use. The effect of reducing the number of point sources per hectare while keeping the amount of pheromone applied per hectare constant on the success of Grapholita molesta (Busck) (Lepidoptera: Tortricidae) mating disruption was investigated with Confuse-OFM, paraffin disk, and Isomate-M Rosso dispensers. For all dispensers, as point source density decreased, numbers of moths captured increased, percentage of orientation disruption to traps decreased, and variability in these measures increased. Decreasing point source density, even while keeping the amount of pheromone applied per hectare constant is not a viable option for reducing the cost of G. molesta mating disruption with hand-applied dispensers. Puffers (aerosol dispensers) are applied at 2.5-5 dispensers per ha for G. molesta control. However, hand-applied dispensers fail when clumped at such low numbers of release sites. Potential explanations for the success of Puffers and the failure of hand-applied dispensers at very low point source densities are presented. The utility of paraffin disk dispensers as experimental devices also is discussed.

Knowledge of how insects are actually affected by sex pheromones deployed throughout a crop so as to disrupt mating has lacked a mechanistic framework sufficient for guiding optimization of this environmentally friendly pest-control tactic. Major hypotheses are competitive attraction, desensitization, and camouflage. Working with codling moths, Cydia pomonella, in field cages millions of times larger than laboratory test tubes and at substrate concentrations trillions of times less than those typical for enzymes, we nevertheless demonstrate that mating disruption sufficiently parallels enzyme (ligand) -substrate interactions so as to justify adoption of conceptual and analytical tools of biochemical kinetics. By doing so, we prove that commercial dispensers of codling moth pheromone first competitively attract and then deactivate males probably for the remainder of a night. No evidence was found for camouflage. We generated and now validate simple algebraic equations for attraction and competitive attraction that will guide optimization and broaden implementation of behavioral manipulations of pests. This analysis system also offers a unique approach to quantifying animal foraging behaviors and could find applications across the natural and social sciences.

We studied the timing of reproductive maturity of cherry fruit fly, Rhagoletis cingulata (Loew), a key pest of sweet and tart cherries in the eastern United States. To determine when cherry fruit fly females become reproductively mature in managed and natural habitats, we deployed traps in sweet and tart cherry orchards and nearby stands of the ancestral host tree, black cherry. Flies were removed from the traps and females were dissected to determine the presence of fully developed eggs. We found that capture of reproductively mature female flies occurred earlier in orchards that are not sprayed with insecticides than in sprayed orchards or in black cherry tree sites. In addition, the gap between the flights of immature and mature females in unmanaged sweet or tart cherry orchards was shorter than in managed orchards or black cherry tree sites. We also determined fruit color, size, and skin hardness to characterize the progression of fruit maturity. We found that fruit became mature earlier in sweet and tart cherry orchards than in black cherry tree sites. This study indicates that the timing of female reproductive maturity is plastic and varies among cherry fruit fly populations present in distinct habitats. Variation in the timing of reproductive maturity is related to the fruit maturity period of distinct host plant species and to orchard management.

In regions with a humid summer climate, the use of water-soluble bait to control apple maggot is often limited by rainfall. We studied increasing the rainfastness of GF-120 fruit fly bait by adding paraffin wax emulsion. First, we verified that adding 10% wax to a mixture containing 16.7% GF-120 did not reduce the mortality of female apple maggot compared with GF-120 without wax. In addition, we determined that fly mortality caused by GF-120 plus wax subjected to simulated rain was similar to that caused by GF-120 without wax not subjected to rain. Other assays showed that higher fly mortality resulted from increasing the proportion of wax from 10 to 15%, and lower mortality resulted from decreasing GF-120 from 16.7 to 10 or 5%. The availability of spinosad on or near droplets of a mixture consisting of 5, 10, or 15% GF-120 and 15% wax was determined before and after the droplets were subjected to three 15-min periods of simulated rain. We found an initial steep decline in dislodgeable spinosad and smaller decreases after subsequent periods of rain. In a small-plot field trial, fruit infestation by apple maggot in plots treated with a mixture consisting of 16.7% GF-120 and 19.2% wax was less than in plots treated with 16.7% GF-120 without wax but not less than in control plots. Overall, we found that adding paraffin wax emulsion to GF-120 increased rainfastness in laboratory bioassays, and specifically that it retained the active ingredient spinosad. However, our field data suggest that optimal rainfastness requires the development of mixtures with > 19.2% wax, which may preclude application using standard spray equipment.

The effect of delayed mating on reproductive potential, longevity and oviposition period of female redbanded leafroller, Argyrotaenia velutinana (Walker) and Pandemis leafroller, Pandemis pyrusana Kearfott, was investigated in the laboratory. Virgin female or male moths of each species were held for 1, 2, 4, 6 or 10 days prior to pairing with one-day-old virgin conspecifics of the opposite sex. In addition, reproductive potential was assessed when both sexes of each species were aged for those periods prior to pairing. The expected reproduction of female A. velutinana was reduced by 34, 53, 71 and 81% for 2, 4, 6 and 10-day delays in female mating, respectively. For P. pyrusana, expected reproduction was reduced by 47, 74, 85 and 93% for 2, 4, 6 and 10-day delays in female mating, respectively. Increasing male age at mating in both species had a lesser effect on female reproductive output compared with increasing female age at mating. As male A. velutinana age at mating increased, the expected reproduction of female A. velutinana was reduced by 15, 45, 54 and 70% for 2, 4, 6 and 10-day delays, respectively. Comparing male P. pyrusana of various ages at mating, expected reproduction was reduced by 14, 42, 64 and 79% for 2, 4, 6 and 10-day delays in mating, respectively. The decrease in female reproduction when both sexes were aged prior to mating was higher than when either sex alone was aged prior to pairing with a one-day-old virgin of the opposite sex. The expected reproduction of female A. velutinana was reduced by 60, 83, 96 and 98% for 2, 4, 6 and 10-day delays in mating of both sexes, respectively. Only 7.5% of female eggs hatched when both sexes of A. velutinana were aged ten days prior to mating. When simultaneously aging both sexes of P. pyrusana prior to mating, expected reproduction was reduced by 71, 93, 96 and 99% for 2, 4, 6 and 10-day delays in mating, respectively. No P. pyrusana eggs hatched after a ten-day delay of mating for both sexes. For both species, female longevity increased and duration of oviposition period decreased with increasing female age at mating. Our results demonstrate that delayed mating in both females and males negatively affects female reproductive output in both species and that simultaneous aging of both sexes prior to mating has a greater effect than aging either sex alone. Our results suggest that laboratory studies that have paired aged females or aged males with conspecifics of optimal reproductive maturity have likely underestimated the effects of delayed mating on reproductive output.

Five formulations of controlled release, polyethylene tube dispensers of pheromone were evaluated during three field seasons for disruption of codling moth, Cydia pomonella (L.) (Lepidoptera: Tortricidae), and the oriental fruit moth, Grapholita molesta (Busck) (Lepidoptera: Tortricidae). Evaluations were conducted in replicated 4-ha plots of commercial apple in Michigan. Disruption of both C. pomonella and G. molesta male orientation to pheromone traps in plots treated with a dual-species formulation (Isomate CM/OFM TT), simultaneously releasing the pheromone components of both C. pomonella and G. molesta, was equivalent to that obtained by treating plots with separate formulations for each species (Isomate C Plus or Isomate C TT for C. pomonella and Isomate M Rosso for G. molesta) through mid-season. However, disruption efficacy of the dual-species formulation was significantly lower near the end of the season for G. molesta compared with the Isomate M Rosso formulation because of depletion of active ingredients and coincided with a slight increase in fruit injury. Effective disruption of C. pomonella and G. molesta also was obtained with a multispecies formulation (Isomate CM/OFM/LR) that releases the main pheromone components of C. pomonella, G. molesta, and several leafroller species. Each formulation type releasing (E,E)-8,10-dodecadien-1-ol (codlemone) also was found to release the E,Z- and Z,E-isomers of codlemone. Our data provide further evidence that simultaneous disruption of C. pomonella and G. molesta with dispensers releasing both species' pheromone components is possible; however, the controlled release formulations tested here require modification or postponed deployment coupled with early season control by other means to achieve season-long efficacy. Simultaneous disruption of several species with a single formulation will be economically advantageous in regions where control of multiple pests is needed given the need for hand application of this technology.

Background: Chlorantraniliprole formulated as a 350 g kg(-1) WG (Altacor 35WG) for management of apple maggot Rhagoletis pomonella (Walsh), blueberry maggot R. mendax Curran and cherry fruit fly R. cingulata (Loew) (Diptera: Tephritidae) was evaluated in laboratory assays and field trials., Results: A tarsal contact toxicity bioassay showed that a surface residue of 500 mg L(-1) of chlorantraniliprole caused significantly higher mortality of male and female flies of all species compared with a control. Male apple maggot and blueberry maggot mortality was significantly higher than that for females, but there was similar mortality of male and female cherry fruit flies. An ingestion toxicity bioassay showed that 500 mg L(-1) of chlorantraniliprole in diet caused significantly higher mortality of male and female flies of all species than the control, but there were no significant differences among the sexes. Delayed egglaying by females that had ingested chlorantraniliprole was found, but there were no significant sublethal effects on either the number of eggs laid or the egg hatch. Field trials with apple maggot and cherry fruit fly showed that protection of fruit by chlorantraniliprole was comparable with that of standard broad-spectrum insecticides., Conclusions: The present data indicate that chlorantraniliprole has suppressant activity against Rhagoletis fruit flies, preventing fruit infestation primarily through direct lethal effects.

Background: The codling moth is one of the principal pests of apple in the world. Resistance monitoring is crucial to the effective management of resistance in codling moth. Three populations of codling moth in neonate larvae were evaluated for resistance to seven insecticides via diet bioassays, and compared with a susceptible population. In addition, apple plots were treated with labeled field rate doses of four insecticides. Treated fruit were exposed to neonate larvae of two populations from commercial orchards., Results: Two populations of codling moth expressed two- and fivefold resistance to azinphos-methyl, seven- and eightfold resistance to phosmet, six- and tenfold resistance to lambda-cyhalothrin, 14- and 16-fold resistance to methoxyfenozide and sixfold resistance to indoxacarb, but no resistance to acetamiprid and spinosad. The impact of the resistance to azinphos-methyl, measured as fruit damage, increased as the insecticide residues aged in the field. In contrast, fruit damage in methoxyfenozide- and lambda-cyhalothrin-treated fruit was observed earlier for resistant codling moth. No differences in efficacy were found for acetamiprid., Conclusions: Broad-spectrum insecticide resistance was detected for codling moth. Resistance to azinphos-methyl, lambda-cyhalothrin and methoxyfenozide was associated with reduced residual activity in the field. Broad-spectrum resistance presents serious problems for management of the codling moth in Michigan.

Flight periods of the cherry fruit fly, Rhagoletis cingulata (Loew), were compared in the major sweet and tart cherry-growing regions of Michigan, among neglected orchards, managed orchards, and natural areas containing the ancestral host, black cherry. Traps were deployed from early June to late September 2005 and 2006. Captures indicated that cherry fruit fly has an early flight (June-July) in neglected orchards, a mid-season flight peaking immediately after harvest (June-August) in managed orchards, and an extended flight covering most of the season (June-September) in natural areas. We found that the period of fruit infestation mirrored the flight period in neglected and managed orchards. In natural areas, we found infestation late in the season only. The relative emergence periods for adults reared from pupae collected from the three habitats and maintained under the same conditions coincided with adult flight periods for each habitat. We also studied factors related to fruit availability that may have a role in shaping the flight periods. Fruit abundance decreased rapidly early in the season in neglected orchards, whereas in managed orchards, fruit left after harvest remained on the trees until late August. Measurements of fruit size and skin firmness revealed that fly activity in neglected and managed orchards began immediately after fruit increased in size and skin firmness decreased, whereas in natural areas, the flight began before fruit matured. In managed orchards, fruit harvest and insecticide sprays likely maintain the late flight period of resident fly populations by preventing the use of fruit earlier in the season. However, a significant proportion of these resident flies may still emerge before harvest and increase the risk of costly fruit infestation.

Female obliquebanded leafrollers, Choristoneura rosaceana (Harris), collected from Oregon, Michigan, and New York were deployed in delta traps in Michigan apple orchards to compare their relative attractiveness to Michigan males of the same species. Females originating from Oregon attracted more males than females originating from New York during both generations of leafroller flight in Michigan. Also, females from Oregon attracted more males in Michigan than did "native" Michigan females during the first generation of flight. Analysis of gland extracts from the three populations revealed significantly more of each pheromone component in females originating from Oregon (approximately nine-fold more pheromone per female overall) than those from Michigan. However, there were no significant differences in the relative amounts of each pheromone component between Oregon and Michigan females. A 100:4:5:2 blend of Z11-14:OAc, E11-14:OAc, Z11-14:OH, and Z11-14:Ald was optimal for catching males in Michigan with no added or detrimental effect of Z11-14:Ald, confirming previous studies. However, 100:1 ratios of Z11-14:OAc relative to either E11-14:OAc or Z11-14:OH (also containing 2% Z11-14:Ald) captured more males in Oregon apple orchards compared with 100:4 and 100:10 ratios of Z11-14:OAc relative to either E11-14:OAc or Z11-14:OH. Addition of increasing amounts of Z11-14:Ald relative to Z11-14:OAc (range, 0-8:100) into a blend also containing 4% E11-14:OAc and 5% Z11-14:OH increased male catch in Oregon but not in Michigan. Our results suggest that pheromone blend quantity rather than blend quality may explain greater attractiveness of western compared with eastern female C. rosaceana to males in Michigan. Also, an optimized generic blend for monitoring male C. rosaceana across North America should contain Z11-14:Ald as has been previously shown, but should not exceed 4:100 ratios of both E11-14:OAc and Z11-14:OH relative to Z11-14:OAc for optimized catch of males in the western United States.

Several application parameters of microencapsulated (MEC) sex pheromone formulations were manipulated to determine their impact on efficacy of disruption for codling moth, Cydia pomonella (L.); oriental fruit moth, Grapholita molesta (Busck); obliquebanded leafroller, Choristoneura rosaceana (Harris); and redbanded leafroller, Argyrotaenia velutinana (Walker). Depending on the experiment, the formulations evaluated were those formerly manufactured by 3M Canada (London, ON, Canada) or those that are currently available from Suterra LLC (Bend, OR). The efficacy of MEC formulations applied by air-blast sprayer evenly throughout the entire canopy of 2-3-m-tall apple (Malus spp.) trees was equivalent to treatments in which targeted applications of MECs were made to the lower or upper 1.5 m of the canopy (at equivalent overall rates) for oriental fruit moth and both leafroller species. The realized distribution of deposited microcapsules within the tree canopy corresponded well with the intended heights of application within the canopy. The additional coapplication of the pine resin sticker Nu-Film 17 increased efficacy but not longevity of MEC formulations for oriental fruit moth; this adjuvant had no added effects for codling moth or leafroller formulations. Increasing the rate of active ingredient (AI) per hectare by 20-30-fold (range 2.5-75.0 g/ha) did not improve the disruption efficacy of MECs for codling moth or either leafroller species when both low and high rates were applied at equivalent frequencies per season. A low-rate, high-frequency (nine applications per season) application protocol was compared with a standard protocol in which two to three applications were made per season, once before each moth generation for each species. The low-rate, high-frequency protocol resulted in equivalent or better disruption efficacy for each moth species, despite using two-fold less total AI per hectare per season with the former treatment. The low-rate, frequent-application protocol should make the use of MEC formulations of synthetic pheromone more economical and perhaps more effective.

The University of California at Davis patented the use of emulsified wax to release pheromones for mating disruption. Advantages of these dispensers include low cost, self-adhesion, and biodegradation. We compared the efficacy and practicality of Confuse-OFM, a commercial emulsified wax formulation of oriental fruit moth, Grapiholita molesta (Busck), pheromone with those of Check-Mate OFM-F sprayable pheromone and Isomate-M 100 polyethylene tube dispensers in commercial peach (Prunus spp.) orchards. Efficacy was measured with male captures in pheromone-, virgin female-, and liquid attractant-baited bucket traps as well as by noting injury to shoots and fruit. Two applications of Confuse-OFM were as effective as two applications of CheckMate OFM-F and one application of Isomate-M 100. However, Confuse-OFM was tedious to apply and wasted pheromone with an initially high release rate. We developed a new emulsified wax formulation (Wax Dollops) that maintained release rates above a 5 mg/ha/h threshold twice as long as Confuse-OFM in the laboratory. Field trials confirmed that one application of 3-ml dollops (590 dollops per ha) provided season-long (approximately 15 wk) control equivalent to that of Isomate-M 100 and Confuse-OFM applied as described above. Several applicators were developed for Wax Dollops, including a pneumatic gun that shot dollops >2 m. However, the most efficient method for application was wiping dollops onto tree branches by using a flat-bladed spatula. This research was the basis for a new line of commercial pheromone pest control products equally effective to current commercial formulations but with advantages in cost and flexibility.

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.

Residue profile analysis techniques were developed, along with laboratory and field-based bioassays to describe the modes of insecticidal activity responsible for the control of the plum curculio, Conotrachelus nenuphar (Herbst), in apples (Malus spp.). Adult plum curculios were treated in laboratory topical bioassays to determine acute contact activity and lethal time for five insecticides. Azinphosmethyl had the highest levels of toxicity and shortest lethal time values, followed by the neonicotinoids thiacloprid, thiamethoxam, and imidacloprid, whereas indoxacarb had the highest LD50 and LT50 values for topical exposure. Field-based residual activity bioassays assessed adult mortality, and fruit and leaf injury from plum curculio exposed to 4 h, 7 d, and 14 d field-aged residues. All compounds caused significant levels of mortality to plum curculio when adults were exposed to fruit clusters 4 h post-application. Thiacloprid, thiamethoxam, and imidacloprid showed oviposition deterrence, antifeedant, and repellency effects in the 7- and/or 14 d residual bioassays and protected fruit in the absence of significant lethal activity. Indoxacarb maintained lethal activity throughout the study intervals, with the incidence of plum curculio feeding, suggesting that ingestion is an important mode of entry. For the neonicotinoids thiacloprid, thiamethoxam and imidacloprid plum curculio mortality was highly correlated with fruit and leaf surface residues. As surface residues declined, sublethal effects such as oviposition deterrence and antifeedant effect remained. The value of the plant-insect-chemistry triad model for describing the temporal dimensions of insecticidal modes of activity and understanding a compound's critical performance characteristics is discussed.

Eleven out of 13 disruption profiles (plots of dispenser density vs. male catch) from moth sex pheromone literature were consistent with a competitive-attraction mechanism, in which dispensers attract males and thereby divert them from females. Mean dispenser activity (D(a)) across all competitive-attraction cases was 0.04 +/- 0.06 (SD); values ranged from 0.0005 for a tiny laminated flake dispenser of racemic disparlure targeting gypsy moth to 0.2 for polyethylene tube dispensers used against lightbrown apple moth. A dispenser application activity (D(Aa)) can be calculated by multiplying D(a) by the number of such dispensers applied per hectare of crop. The highest dispenser application activity (D(Aa)) values approached 200 and corresponded to >99% inhibition of catches of male moths in monitoring traps. Relative to the D(Aa) scale, % inhibition of catches of male moths compressed and obscured large differences in D(Aa) when % disruption exceeded 90%. For cases of competitive attraction, these two efficacy scales can be interconverted by using the formula: D(Aa) approximately = 100/(100 minus % disruption). When disruptive point sources of pheromone were directly observed, male moths were seen approaching pheromone dispensers whose disruption profiles matched competitive attraction. Two cases fit non-competitive disruption mechanisms, which include camouflage, desensitization (adaptation and/or habituation), and sensory imbalance. In these cases, pheromone was released at rates higher than for cases of disruption by competitive attraction. Practical ramifications of the finding that competitive attraction appears to be the prevalent mechanism for moth mating disruption by pheromone point sources are listed. We believe that the congruence of diverse sets of mating disruption field data with explicit a priori predictions validates competitive-attraction theory. The analytical tools and principles governing competitive attraction that were uncovered during this study of mating disruption of moths should be generally applicable to competitive-attraction phenomena.

A tractor-mounted mechanized applicator was developed for large-scale deployment of paraffin-wax dispensers of pheromone for mating disruption of oriental fruit moth, Grapholita molesta (Busck). The wax formulation was mostly water and emulsified paraffin wax containing 5% (by weight) pheromone [93:6:1 blend of (Z)-8-dodecen-1-yl-acetate:(E)-8-dodecen-1-yl-acetate: (Z)-8-dodecen-1-ol]. Ten milliliters of wax was applied per tree as approximately 160 deposits (0.04 ml of wax per drop). An average of 23 min was required to treat 1 ha of crop. Disruption efficacy of mechanically applied wax was measured relative to an untreated control in replicated 0.4-ha blocks within a recently abandoned apple orchard. From 6 May to 27 June, 100% disruption of tethered virgin females and 97% inhibition of pheromone traps was achieved for 52 d with two applications of wax. However, during mid- to late summer (July-August), this level of efficacy was maintained for only approximately 1 wk after each of two applications. Higher temperatures later in the season may have accounted for abbreviated efficacy of the applied small drops. Mechanically applied paraffin-wax technology may increase adoption of mating disruption given that a higher level of efficacy was achieved despite deploying less active ingredient per hectare relative to that used with reservoir dispensers. The savings in labor by not requiring hand application of reservoir dispensers could be directed toward cost of machinery. However, the short duration of efficacy obtained with the current wax formulation and mechanical applicator is judged uneconomical given the eight or more applications that would have been required for high-performance disruption over the full season. Larger drops with lower surface area-to-volume ratios are expected to prolong pheromone release for extended efficacy and desirable overall economics.

This study establishes a theoretical framework for differentiating among possible behavioral mechanisms whereby sexual communication of moths is disrupted in crops treated with point sources of pheromone. The major mechanisms recognized in the mating disruption literature fall into two main categories: competitive (competitive attraction = false-plume-following) and non-competitive (camouflage, desensitization, and sensory imbalance). Each disruption mechanism has been precisely defined verbally, and then the distinguishing characteristics of the two categories were defined mathematically. The sets of predictions associated with each category were visualized by graphical plots of mathematical simulations. Profiles of simulated male visitation rates to pheromone-baited traps deployed in pheromone-treated crops were graphed against density of pheromone dispensers by using various types of axes. Key traits of non-competitive attraction are as follows: concave profiles on untransformed axes, with an asymptotic approach to zero catch of male moths in traps; a straight line with positive slope when 1/catch is plotted against dispenser density (Miller-Gut plot); and a straight line with negative slope when catch is plotted against dispenser density * catch (Miller-de Lame plot). Key traits of non-competitive disruption profiles include: an initial linear disruption profile on untransformed axes; a concave Miller-Gut plot; and a recurving Miller-de Lame plot. These differences in profiles provide a basis for distinguishing competitive from non-competitive mechanisms when analyzing disruption profiles from field experiments. Slopes and intercepts of these secondary plots can also reveal both male and female moth densities, if the relative attractiveness of traps, females, and dispensers is known. The absolute value of the slope of the Miller-de Lame plot is a measure of each dispenser's activity (D(a)) for suppressing catch of male moths in traps. An application activity (D(Aa)) for a given dispenser can be calculated by multiplying D(a) by the number of such dispensers applied per hectare of crop.

GF-120 is a baited formulation of the insecticide spinosad containing 1% ammonium acetate, developed for control of economically important fruit flies. The response of feral cherry fruit flies, Rhagoletis cingulata Loew, to GF-120 augmented with 0, 5, or 10% ammonium acetate was evaluated under orchard conditions. Significantly more flies were observed within 30 cm of bait droplets with 10% ammonium acetate added compared with standard bait or to a water control. These fly visits to GF-120 enhanced with 10 or 5% ammonium acetate lasted an average of 263.2 +/- 85.2 and 337.6 +/- 72.6 s, respectively, compared with 50.3 +/- 36.4 s for standard GF-120. Droplets containing additional ammonium acetate also were contacted by more flies, and more flies fed upon these droplets than on GF-120 or the water control. Furthermore, the duration of feeding on GF-120 bait enhanced with either level of additional ammonium acetate was significantly greater compared with standard GF-120 or water. Feeding events lasted between 61.5 +/- 30.7 and 73.4 +/- 21.0 s on enhanced GF-120 compared with 6.8 +/- 5.7 s on standard GF-120. Collectively, these results indicate that the interaction of feral R. cingulata with GF-120 droplets and the toxicant spinosad can be increased by addition of ammonium acetate.

Field experiments quantified the effect of synthetic pheromone release-site density and distribution on 1) orientational disruption of male codling moths, Cydia pomonella (L.) (Lepidoptera: Tortricidae), to pheromone-baited traps; and 2) fruit injury. A clustering test varied pheromone release-site density from 0 to 1,000 Isomate-C Plus dispensers per ha while maintaining the total number of dispensers at 1,000. Percentage of orientational disruption of pheromone-baited traps increased significantly as a function of increasing density of release sites. Fruit injury decreased as the density of release sites increased and was lowest in plots treated with Isomate-C Plus dispensers distributed as 1,000 point sources per ha. We also manipulated point source density of 0.1-ml paraffin-wax drops containing 5% codlemone [(E,E)-8,10-dodecadien-1-ol], and thus the total amount of pheromone deployed per hectare. The percentage of disruption of traps baited with either 1.0- or 0.1-mg codlemone lures increased with increasing density of wax drops deployed. Both trapping and field observations confirmed that wax drops were attractive to male codling moths, suggesting that disruption was mediated by competitive attraction. Development of dispensers that can be mechanically applied at high densities has potential to improve the efficacy and economics of codling moth disruption at high population densities.

The effect of brief pheromone exposures on responses of codling moth (Cydia pomonella L.) males was tested by flight-tunnel and electroantennogram (EAG) studies. Males were preexposed to pheromone for up to 3 min as they sat in release cages or for shorter times (a few seconds to several min) upon initiating flights or orienting in plumes. Brief exposures to Isomate-C Plus dispensers nearly eliminated moth orientations to 0.1 mg codlemone [(E,E)-8,10-dodecadien-1-ol] and 0.1 mg three-component (codlemone/12OH/14OH, 100:20:5 ratio) lures 15 min later. However, there was no associated change in EAG responses between preexposed and control moths. Behavioral responses of Isomate-C Plus-exposed males were normal 24 hr following exposure. The reduced sexual responsiveness observed following exposure to Isomate dispensers appeared to be associated with an elevation of response threshold. Brief preexposure to 0.1 mg codlemone and three-component lures also reduced orientational behavior of males 15 min later, but to a lesser degree than when preexposed to Isomate-C Plus dispensers. Male behavior following preexposure to a 0.1 mg codlemone/pear ester [(2E,4Z)-2,4-decadienoate] lure (1:1 ratio) was no different from exposure to codlemone only. Orientational disruption in plots treated with 10 dispensers of Isomate-C Plus per tree was 88.3 and 95.9% for 1.0 and 0.1 mg codlemone lures, respectively. Some males did orient to 0.1 mg codlemone lures so we caution that flight-tunnel experiments on preexposure may overestimate the actual pheromone exposure dosage received by feral moths in treated orchards. Importantly, this work documents that a portion of feral males within a population has the capacity to overcome communicational disruption by high densities of Isomate-C Plus dispensers.

In 2004 field experiments, we compared the effectiveness of various deployment densities of 0.1-ml paraffin wax drops containing 5% pheromone versus Isomate M-Rosso "rope" dispensers for disruption of Grapholita molesta (Busck). Treatments were evaluated in 0.05-ha (12-tree) plots of 'Delicious' apples receiving regular maintenance according to growers' standards, but not sprayed with insecticides. The application densities of 0.1-ml wax drops were 3 per tree (820/ha), 10 per tree (2,700/ha), 30 per tree (8,200/ha), and 100 per tree (27,300/ha). Wax drops were compared with 3-ml dispensers of pheromone-containing paraffin wax or Isomate M-Rosso ropes at 1.8 per tree (500/ha) and untreated control plots. Treatments were applied before the start of each of three moth generations. Orientational disruption, as measured by inhibition of moth captures in pheromone-baited delta traps, was greatest in plots that received 100 drops per tree (99.2%) and 30 drops per tree (99.4%). More than 55% of tethered, virgin females were mated in control plots after one night of deployment. However, no mating was recorded at the two highest application densities of wax drops where orientational disruption of traps exceeded 99%. Mating ranged from 7 to 20% among the other treatments, including Isomate rope dispensers. G. molesta males were observed closely approaching pheromone dispensers in plots containing ropes and wax drops, documenting competitive attraction between synthetic pheromone sources and feral females. The majority of observed G. molesta males approached within 60 cm of wax drops or pheromone ropes and departed within 20 s by flying upwind. Thirty wax drops per tree yielded higher mating disruption of G. molesta than did Isomate M-Rosso dispensers deployed at the recommended rate of 500/ha (1.8 per tree). Measurement of release rates confirmed behavioral data indicating that paraffin wax dispensers would need to be applied once per G. molesta generation in Michigan. Paraffin wax drops are a promising technology for moth mating disruption. They are cheaper and easier to produce, require less total pheromone per annual application, and produce better mating disruption at appropriate deployment densities compared with Isomate M-Rosso dispensers under high G. molesta population densities. The cost-effectiveness of this approach will require an appropriate mechanized applicator for wax drops.