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. Mating disruption of insects is the agricultural practice of dispensing synthetic sex attractant into a crop so as to suppress pest reproduction by interfering with mate finding (1). The Environmental Protection Agency expects this environmentally friendly pest management tactic to effectively supplement the "softer" insecticides as well as to fill critical control gaps left as "harder" insecticides face withdrawal from the marketplace due to tightening governmental regulations (2-4), e. g., azinphos methyl (Guthion) in apple production. There are now more than 100 EPA registrations of insect pheromones for use as pest control agents in agriculture and forestry. Mating disruption for all pests encompasses ≈700,000 ha (5), 160,000 of which target codling moth, Cydia pomonella, the proverbial worm in the apple.Despite 40 years of research and the emergence of a vigorous and expanding worldwide pheromone industry (5, 6), knowledge of how sex pheromones actually interact with target insects as individuals and groups under disruption has lacked a mechanistic framework sufficient for judging whether current practices for implementing mating disruption have been optimized. Here, we introduce and experimentally validate both attraction and competitive-attraction equations as well as a unique analysis system. Their utility in understanding and manipulating animal behaviors might parallel those of the Michaelis-Menten equation and classical enzyme kinetics in biochemistry.Derivation of Equations. Wind traversing a pheromone point source sweeps out an odor plume whose active space and interactions with male moths are schematically represented in Fig. 1. Cumulative catch (C) of male moths (♂) in a trap (T) (Fig. S1 presents pictures of apparatus) baited with a pheromone...

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.

A two-year study was conducted evaluating PuVer ® aerosol dispensers (Suterra LLC, Bend, OR, USA) for mating disruption of codling moth, Cydia pomonella (L.), and the oriental fruit moth, Grapholita molesta (Busck). The PuVer ® dispenser consists of a pressurized metal canister loaded with pheromone active ingredients dissolved in solvent and housed within a circuit-controlled, plastic dispensing cabinet programmed to release an aerosol spray of pheromone at regular intervals. PuVers ® were deployed at the label-recommended rate of 2.5 ha ¡1 and released ca. 5-10 mg of pheromone (depending on treatment) per 15 min during a 12-h cycle beginning each day at 15:00 h for the duration of the season. In 2005, commercially-managed apple plots (3.2-4.9 ha) were treated with PuVers ® releasing both species' pheromone simultaneously (dual-species) or with twice the number of adjacentlydeployed PuVers ® (4-6 m apart) releasing each individual species' pheromones (single-species), while maintaining comparable overall release rates of pheromone between these two treatments. Plots 100 m away and not treated with pheromone served as the control. Disruption of male C. pomonella and G. molesta orientation to pheromonebaited traps was 46-75 and 91-98%, respectively, in PuVer ® -treated plots compared with untreated controls.There was no statistical diVerence in moth disruption between plots treated with dual-species and single-species PuVers ® . Fruit injury was not statistically diVerent between PuVer ® -treated plots and control plots not receiving pheromone. In 2006, disruption of male moth orientation to traps was 24-26 and 84-97% in PuVer ® -treated plots (2.9-5.7 ha) for C. pomonella and G. molesta, respectively, compared with untreated controls. During this season, fruit injury was lower in pheromone-treated plots compared with untreated controls at mid-season, but not at pre-harvest. Combining the pheromone of both species into single PuVer ® units did not decrease eYcacy of disruption compared with deploying twice as many PuVers ® releasing a similar amount of each individual species' pheromone suggesting that multi-species disruption using PuVers ® is a viable option. However, we conclude that the eYcacy of disruption attained with low-densities (2.5 ha ¡1 ) of PuVers ® at the moth densities recorded in this study is insuYcient for eVective control of C. pomonella without input of companion insecticides.

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.

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