Gary J. R. Judd

Recent studies have demonstrated that key herbivore-induced foliage volatiles from apple, Malus domestica Borkhausen (Rosaceae), can be attractive to conspecific adult male and female tortricid leafrollers when used together with acetic acid lures. Our study reported here was conducted in Washington State during 2013–2014 and assessed the attractiveness of both sexes of the leafroller, Pandemis pyrusana Kearfott (Lepidoptera: Tortricidae), to blends of acetic acid with phenylacetonitrile. Interestingly, traps baited with phenylacetonitrile plus acetic acid caught significantly more males, females, and total moths than the number of males caught in traps baited with a commercial sex pheromone lure. The evaporation rate of the acetic acid co-lure was shown to be an important factor affecting catches of P. pyrusana with phenylacetonitrile. Adding phenylacetonitrile to traps baited with pear ester, ethyl (E, Z)-2,4-decadienoate and acetic acid significantly reduced both total and female moth catches ... Resumen Estudios recientes han demostrado que volátiles foliares claves inducidos por herbívoros en manzano, Malus domestica Borkhausen (Rosaceae), pueden ser atractivos para hembras y machos adultos conspecíficos de enrolladores tortricidos cuando se usan junto con cebos de ácido acético. Nuestro estudio, descrito aquí, se llevó a cabo en el estado de Washington durante 2013–2014 evaluando la atracción de ambos sexos del enrollador, Pandemis pyrusana Kearfott (Lepidoptera: Tortricidae), a mezclas de ácido acético con fenilacetonitrilo. Curiosamente, las trampas cebadas con fenilacetonitrilo y ácido acético capturaron significativamente más machos, hembras y polillas totales que el número de machos atrapados en trampas provistas de un cebo comercial de feromonas sexuales. Demostrándose que la tasa de evaporación del co-atractante de ácido acético era un factor importante que afectaba las capturas de P. pyrusana con fenilacetonitrilo. La adición de fenilacetonitrilo a las trampas cebadas con éster de pera,...

Spilonota ocellana (Denis and Schiffermüller) (Lepidoptera: Tortricidae) can be a serious pest of organic apples (Malus domestica Borkhausen (Rosaceae)) in British Columbia, Canada. Recent discovery that S. ocellana moths are attracted by a lure combining acetic acid (AA) and benzyl nitrile (BN), identified as a caterpillar-induced apple leaf volatile, provides an opportunity to develop bisexual mass-trapping or monitoring systems. Sticky white delta traps baited with benzyl nitrile (10 mg/red rubber septum) and an acetic-acid co-lure (3 mL AA/3-mm open 8-mL vial) caught significantly more moths than either component alone. Acetic-acid co-lures were weakly attractive but benzyl-nitrile-loaded septa were not attractive. Moth catches with AA+BN lures were unaffected by the size and type of rubber septum used to release benzyl nitrile, but catches increased with increasing loads of benzyl nitrile. Male and total moth catches were maximised using membrane release devices loaded with a mixture of benzyl nitrile and a second caterpillar-induced volatile, 2-phenylethanol (PET), in combination with an acetic-acid co-lure (AA+BN-PET). Female catches with AA+BN-PET and AA+BN lures were equivalent. Placing AA+BN lures in traps baited with female sex pheromone lures reduced male catches, but female catches were unchanged. When sticky liners were replaced weekly, white delta traps baited with AA+BN lures caught more moths than similarly baited white Multipher^®-I bucket traps, or transparent Unitraps^TM. Multipher-I traps with a propylene glycol killing agent (250 mL) caught more moths than those with Vapona insecticide strips. In apple orchards treated with mating disruption sex pheromones, traps baited with AA+BN caught slightly more total moths than traps baited with sex pheromone. Weekly, total male+female moth catches with either AA+BN or sex pheromone lures showed similar seasonal patterns in both untreated and pheromone-disrupted orchards, respectively. Long-lasting release devices and an organic killing agent are needed to develop certified organic mass-trapping technologies for management of S. ocellana with the AA+BN kairomone.

Pandemis limitata (Robinson) (Lepidoptera: Tortricidae) is one of several leaf-feeding caterpillar pests of commercial tree-fruit crops in British Columbia, Canada. Recent discovery that European Pandemis Hübner species are attracted by lures combining acetic acid and the caterpillar-induced apple-leaf volatiles, 2-phenylethanol, and phenylacetonitrile, prompted our examination of P. limitata response to these compounds. Trapping tests in organic apple orchards revealed that neither of these individual benzenoids, nor their binary combination, was attractive. Acetic acid alone was weakly attractive, but more importantly, catches increased significantly when an acetic-acid co-lure was combined with 2-phenylethanol or phenylacetonitrile, individually and together. Catches of male and female P. limitata with acetic acid+2-phenylethanol, or acetic acid+2-phenylethanol+phenylacetonitrile were similar, respectively, and both sexes were caught significantly less often in traps baited with acetic acid+phenylacetonitrile. When combined with acetic-acid co-lures, traps baited with membrane dispensers releasing 2-phenylethanol at ~1 mg/day caught significantly more moths than traps baited with rubber septa lures releasing 2-phenylethanol at ~0.6 mg/day. Moth catches in traps baited with 2-phenylethanol were unaffected when the emission of acetic-acid co-lures was increased from ~28 to 63 mg/day. Catches of male P. limitata in traps baited with sex pheromone were significantly greater than catches in traps baited with acetic acid+2-phenylethanol, or traps baited with a ternary blend of acetic acid+2-phenylethanol+sex pheromone. Catches of female P. limitata in traps baited with acetic acid+2-phenylethanol were significantly reduced when it was combined with sex pheromone. Use of the ternary acetic acid+2-phenylethanol+phenylacetonitrile blend provides an opportunity to develop multispecies bisexual trapping systems to improve management of sympatric tortricid pests currently causing economic losses in organic apples in British Columbia. More work on long-lasting release devices, nonsaturating traps, and organically acceptable killing agents are needed to develop organic mass-trapping systems.

Studies were conducted in commercial apple orchards in British Columbia, Canada, to determine whether lures combining ethyl-(E,Z)-2,4-decadienoate, pear ester (PE), with either acetic acid (AA) or sex pheromone, (E,E)-8,10-dodecadien-1-ol (codlemone), might improve monitoring of codling moth, Cydia pomonella (L.), in an area-wide programme integrating sterile insect technology (SIT) and mating disruption (MD). Catches of sterile and wild codling moths were compared in apple orchards receiving weekly delivery of sterile moths (1:1 sex ratio) using white delta traps baited with either AA or PE alone, and in combination. Sterile and wild codling moths responded similarly to these kairomone lures. For each moth sex and type (sterile and wild), AA-PE lures were significantly more attractive than AA or PE alone. Bisexual catches with AA-PE lures were compared with those of commercial bisexual lures containing 3 mg of codlemone plus 3 mg of PE (Pherocon CM-DA Combo lure, Trécé Inc., Adair, OK, USA), and to catches of males with standard codlemone-loaded septa used in SIT (1 mg) and MD (10 mg) programmes, respectively. CM-DA lures caught the greatest number of sterile and wild male moths in orchards managed with SIT alone, or combined with MD, whereas AA-PE lures caught 2–3× more females than CM-DA lures under both management systems. Sterile to wild (S:W) ratios for male versus female moths in catches with AA-PE lures were equivalent, whereas in the same orchards, male S:W ratios were significantly greater than female S:W ratios when measured with CM-DA lures. Male S:W ratios measured with CM-DA lures were similar to those with codlemone lures. CM-DA and codlemone lures appear to overestimate S:W ratios as measured by AA-PE lures, probably by attracting relatively more sterile males from long range. Using AA-PE lures to monitor codling moths in an SIT programme removes fewer functional sterile males and reduces the need for trap maintenance compared with using codlemone lures. AA-PE lures allow detection of wild female moths that may measure damage potential more accurately than detection of wild males. The short-range activity of AA-PE lures compared with that of codlemone-based lures appears to improve the ability to measure S:W ratios and the impact of SIT on population control near the site where wild moths are trapped.

The codling moth, Cydia pomonella L. (Lepidoptera, Tortricidae), is a major pest of apple, pear and walnut orchards worldwide. This pest is often controlled using the biologically friendly control method known as pheromone-based mating disruption. Mating disruption likely exerts selection on the sexual communication system of codling moth, as male and female moths will persist in their attempt to meet and mate. Surprisingly little is known on the intraspecific variation of sexual communication in this species. We started an investigation to determine the level of individual variation in the female sex pheromone composition of this moth and whether variation among different populations might be correlated with use of mating disruption against those populations. By extracting pheromone glands of individual females from a laboratory population in Canada and from populations from apple orchards in Spain and Italy, we found significant between- and within-population variation. Comparing females that had been exposed to mating disruption, or not, revealed a significant difference in sex pheromone composition for two of the minor components. Overall, the intraspecific variation observed shows the potential for a shift in female sexual signal when selection pressure is high, as is the case with continuous use of mating disruption.

Apple clearwing moth (ACM),Synanthedon myopaeformis(Borkhausen) (Lepidoptera: Sesiidae), is an invasive species and destructive pest of commercial apple trees in British Columbia (BC), Canada. Mass trapping with Concord grape juice and sex pheromone is being developed as an organic pest management tactic. We quantified the diversity and abundance of arthropod by-catch in these traps during the 2009 flight (13 June–31 July) of ACM. Paired traps were deployed in organic and conventionally managed apple orchards planted using different tree densities representing the extremes of the current BC apple industry. Using seasonal by-catch and community-level statistical analyses we determined that family communities of arthropods caught in juice-baited and pheromone-baited traps differed significantly. Yellow juice-baited traps caught a greater variety of arthropod families in greater abundance than pheromone-baited yellow Unitraps^®. We show that for each trap type, family communities caught in organic versus conventional orchards were significantly different. Organic orchard management affected abundance of some beneficial taxa, but the sign of the difference depended on the taxon examined (e.g., ladybeetles increased versus lacewings declined). Tree density had no effect on by-catch. Managing ACM by mass trapping may be detrimental to ecosystem services because many nontarget beneficial species are caught. A balanced risk-to-benefit approach should be taken before this technology is widely implemented against ACM.

Apple clearwing moth, Synanthedon myopaeformis (Borkhausen) (Lepidoptera: Sesiidae), is an invasive species in Canada and a destructive pest of commercial apple trees in British Columbia. Adult mass trapping is being developed to help organic apple producers manage this pest. We manipulated and measured spectral reflectance from delta traps, unitraps, and bottle traps used to deploy sex pheromone, phenylacetaldehyde, and grape juice mass-trapping baits and compared catches in baited traps having different reflectance properties. Synanthedon myopaeformis did not discriminate among pheromone-baited delta traps painted yellow, green, or white, from those left clear (group 1), nor among those painted purple, blue, red, or black (group 2). Catches by all treatments in group 1 were significantly greater than all in group 2. Catches in pheromone-baited delta traps were positively correlated with their intensity of green wavelength reflectance (500–550 nm). Fluorescent yellow delta traps reflected more green and ultraviolet (300–400 nm) light than standard yellow or green traps but caught significantly fewer moths when baited with pheromone, implying an antagonistic interaction of green versus ultraviolet-sensitive behaviours. Pheromone-baited all-yellow unitraps caught significantly more moths than equivalent all-green, all-white, or all-red unitraps. Catches in pheromone-baited all-yellow unitraps decreased when any component (lid, funnel, or bucket) was replaced with a green one. Changing the intensity or quality of reflectance from funnels had the greatest impact on unitrap catches (82% reduction). Spectral preferences were modulated by odours eliciting different behaviours (mating versus feeding). When baited with the floral feeding odour phenylacetaldehyde, yellow and green delta traps were among the least attractive, whereas black and blue traps were among the most attractive. When baited with grape juice food baits, black bottle traps caught significantly more moths than any other colour except white, and the former are recommended for maximising mass trapping of females while minimising nontarget impacts of juice baits.

Raspberry crown borer, Pennisetia marginata (Harris) (Lepidoptera: Sesiidae), is a native North American species and pest of many cane fruits. Using coupled gas chromatographic–electroantennographic detection analyses (GC-EAD) we identified candidate sex pheromone components in pheromone gland extracts and effluvia from calling females. Analysis of gland extracts on a Zebron-5 column revealed four components (A, B, C, and D) that elicited strong responses from male antennae. The two most EAD-active components A and B were hypothesised to be (3E,13Z)-octadecadienal [(3E,13Z)-18:Ald] and (3E,13Z)-octadecadienol [(3E,13Z)-18:OH], respectively. Their retention times on other GC columns matched those of authentic standards, thus supporting structural assignments. Synthetic (3E,13Z)-18:Ald, and its GC rearrangement product (2E,13Z)-octadecadienal [(2E,13Z)-18:Ald; component C], also induced antennal responses in GC-EAD analyses of female effluvia. Compounds D in pheromone gland extract, and E and F in female effluvia, elicited EAD responses but could not be identified. In field trapping experiments, (3E,13Z)-18:Ald was the only component that attracted male P. marginata when tested alone. Attractiveness of (3E,13Z)-18:Ald was reduced when combined in binary or ternary blends with any of the other identified components, suggesting one or all may act as pheromone antagonists. In Aldergrove, British Columbia, Canada, peak diel attraction of male P. marginata to (3E,13Z)-18:Ald occurred between 16:00 and 18:00 hours Pacific Daylight Time, at temperatures of 21–23°C, on 30 August 2010, 3 September 2010, and 13 September 2010. We conclude that (3E,13Z)-18:Ald is the major pheromone component of P. marginata.

Pheromone trap catches and mating activity of sterile, mass-reared, diapaused and non-diapaused male codling moths, Cydia pomonella (L.) (Lepidoptera: Tortricidae), were compared with those of wild diapaused males using mark–release–recapture field experiments in springtime. Sterile moths were provided by the Okanagan–Kootenay Sterile Insect Release (SIR) Program mass-rearing facility, in Osoyoos, British Columbia, Canada. Nondiapause-reared (SIR-standard) and diapause-reared (SIR-diapaused) sterile males were recaptured in similar frequencies. Both types of sterile males were recaptured significantly less often than similarly released wild diapaused males, and ratios of recaptured sterile to wild males were similar with either sterile male. Ratios of sterile to wild males, using the combined catches of SIR-standard and SIR-diapaused males, were significantly lower when measured with traps baited with wild-females (21:1) than with traps baited with 10 μg pheromone (48:1). Both trapping ratios were markedly lower than the 80:1 ratio at which sterile and wild males were released. In mating studies, SIR-standard and SIR-diapaused males exhibited equivalent mating frequencies and both were recaptured in copula with tethered wild females significantly less often than released wild males. In the same mating studies, sterile mass-reared, diapaused males that had been chilled for 3 h at the Pacific Agri-Food Research Centre (PARC) before release (PARC-diapaused) were significantly more competitive than SIR-standard or SIR-diapaused males that averaged 24 h of chilling as part of normal SIR Program operations. PARC-diapaused males and released wild males mated with tethered females with equal frequency. We hypothesize that the length of time SIR males were chilled before being released may have caused SIR-diapaused males to be less mobile, and therefore less competitive with wild males in field mating assays, than were PARC-diapaused males. Based on these results, introduction of a diapause phase into the mass-rearing system used at the Osoyoos facility cannot currently be recommended as a means of improving trap-measured ratios of sterile to wild males, or increasing sterile × wild matings.