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Mealybugs are phloem-feeding insects found on many crops worldwide. In New Zealand vineyards, they transmit the economically important Grapevine leafroll-associated virus 3 (GLRaV-3). For some mealybug species, synthetic sex pheromones have been commercialised, and are used as monitoring tools. The mealybugs Pseudococcus longispinus and Pseudococcus calceolariae are major pests in many New Zealand vineyards. We present work on the development of a combined P. longispinus and P. calceolariae pheromone lure. The optimal dose for monitoring P. longispinus was found to be 10 µg of the (S)-(+)-enantiomer, either alone or in the racemic mixture. Addition of the corresponding alcohol did not improve trap catch of P. longispinus. Both the P. longispinus and the P. calceolariae pheromone lures remained active in the field for 90 days. Combining the 2 species’ pheromones had no negative effects on male mealybug trap catch for either species. We conclude that the pheromone ester alone is the best lure for the male P. longispinus. Combining the two mealybug species’ pheromones into a single lure provides the New Zealand viticultural industry with an efficient monitoring tool. Late-vintage deployment of baited lures will provide information on mealybug abundance and local distribution that will inform the scope of future insecticide programmes, to target areas based on need rather than an area-wide application by default.

Social wasps are amongst the most loathed exotic predators in New Zealand, with widespread adverse impacts on native ecosystems and fauna. Sustainable alternatives to pesticides are sorely needed i...

Eradication of new pests can avoid ongoing management costs. Although predominantly employed for suppression, classical biological control (CBC) may support eradication attempts, but also may cause non-target impacts in the long term. While CBC is potentially less costly than other approaches, complete eradication is difficult, especially when pests can sustain their populations at low levels. The sterile insect technique (SIT) involves the mass-rearing and release of sterilised insects to disrupt fecundity. This has proven to be synergistic with the release of biological control agents such as egg parasitoids. Here we describe a newly conceptualised tool, the ‘Kamikaze Wasp Technique’ (KWT), which uses a novel combination of CBC and SIT in an eradication to avoid impacts on non-target organisms. This technique proposes the release of sterile parasitoids, as irradiating mated female parasitoids can induce sterility without inhibiting their ability to kill the host. Future work should characterise the irradiation biology of parasitoids. Halyomorpha halys Stal (Hemiptera: Pentatomidae) and its natural enemy, Trissolcus japonicus Ashmead (Hymenoptera: Scelionidae), provide a model system for assessing the potential of the KWT.

The spotted-wing drosophila (SWD), Drosophila suzukii Matsumura (Diptera: Drosophilidae), native to Eastern Asia, is an invasive alien species in Europe and the Americas, where it is a severe pest of horticultural crops, including soft fruits and wine grapes. The conventional approach to controlling infestations of SWD involves the use of insecticides, but the frequency of application for population management is undesirable. Consequently, alternative strategies are urgently needed. Effective and improved trapping is important as an early risk detection tool. This study aimed to improve Droskidrink&reg, (DD), a commercially available attractant for SWD. We focused on the chemical and behavioral effects of adding the bacterium Oenococcus oeni (Garvie) to DD and used a new trap design to enhance the effects of attractive lures. We demonstrate that microbial volatile compounds produced by O. oeni are responsible for the increase in the attractiveness of the bait and could be later utilized for the development of a better trapping system. Our results showed that the attractiveness of DD was increased up to two-fold by the addition of commercially available O. oeni when combined with an innovative trap design. The new trap-bait combination increased the number of male and especially female catches at low population densities.

This project investigated how kairomone lures, camera traps, and counting software could together contribute to pest management. Images of cumulative daily catch of New Zealand Flower Thrips (NZFT) attracted to a ripe peach lactone (6-pentyl-2H-pyran-2-one, 6-PAP) were automatically loaded to the internet and compared with scanned bases checked weekly using in-house software and manual counting. Camera traps were able to provide thrips counts equivalent to delta traps, but daily and remotely. An 11-fold greater NZFT count occurred within 24 h in passive traps after polyethylene sachets loaded with 250 mg of 6-PAP were placed in trees. Intensive trapping, by placing 1, 2, 4, and 8 traps per tree (500 mg/trap), resulted in a maximum 32-fold increase in thrips per tree. While 6-PAP has proved to be a useful tool for monitoring NZFT numbers, our results suggest that it is not likely to be suitable for mass trapping. Future research should investigate NZFT behavior to better understand population movement on an area-wide basis. Camera traps can be a valuable tool for recording insect flight activity remotely, but the number of traps required for statistically reliable estimates may be prohibitive.

Mealybugs damage a variety of crops worldwide, vectoring viruses and causing problems from sooty mould. The identification of the citrophilous mealybug (Pseudococcus calceolariae, CMB) fema...

Epiphyas postvittana is a major horticultural pest in many countries, including New Zealand. Recently, two minor components (E)-11-tetradecen-1-ol and (E)-11-hexadecenyl acetate were found to increase the attraction of a previously identified two-component sex pheromone (95:5 blend of (E)-11-tetradecenyl acetate [E11-14:Ac] and (E,E)-9,11-tetradecadienyl acetate [E9,E11-14:Ac]) of Epiphyas postvittana. We hypothesised that the interaction between these minor components and the behavioural antagonist (Z)-11-tetradecenyl acetate (Z11-14:Ac) would modulate its antagonistic effect. The effect of increasing the ratio (0.5—10%) of Z11-14:Ac was tested in traps baited with E11-14:Ac and E9,E11-14:Ac (95:5), with or without the addition of the two minor compounds. Catch decreased as the percentage of Z11-14:Ac increased (χ2=108.74; d.f.=9; P

Habituation to sex pheromones is one of the key mechanisms in mating disruption, an insect control tactic. Male moths often show reduced sexual response after pre-exposure to female sex pheromone. Mating disruption is relatively rare in insect orders other than Lepidoptera. As a positive control we confirmed habituation in a moth (Epiphyas postvittana) using 24 h pre-exposure to sex pheromone to reduce subsequent activation behaviour. We then tested the impact of pre-exposure to sex or trail pheromone on subsequent behavioural response with insects from three other orders. Similar pre-exposure for 24 h to either sex pheromone (Pseudococcus calceolariae (Homoptera) and apple leaf curling midge Dasineura mali (Diptera), or trail pheromone of Argentine ants (Linepithema humile (Hymenoptera)), followed by behavioural assay in clean air provided no evidence of habituation after pre-exposure in these latter cases. The moths alone were affected by pre-exposure to pheromone. For pests without habituation, sustained attraction to a point source may make lure and kill more economical. Improved knowledge of behavioural processes should lead to better success in pest management and mechanisms should be investigated further to inform studies and practical efforts generally enhancing effectiveness of pheromone-based management.

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 of codling moth, Cydia pomonella (L.) (Lepidoptera: Tortricidae). However, neither C. pomonella nor P. pyrusana catch were impacted when phenylacetonitrile and acetic acid were added to traps baited with pear ester plus (E, E)-8,10-dodecadien-1-ol, the sex pheromone of codling moth. These results support our broader work to develop lures to improve monitoring and management of a number of tortricid pests attacking horticultural crops worldwide. Resumen Estudios recientes han demostrado que volatiles foliares claves inducidos por herbivoros en manzano, Malus domestica Borkhausen (Rosaceae), pueden ser atractivos para hembras y machos adultos conspecificos de enrolladores tortricidos cuando se usan junto con cebos de acido acetico. Nuestro estudio, descrito aqui, se llevo a cabo en el estado de Washington durante 2013-2014 evaluando la atraccion de ambos sexos del enrollador, Pandemis pyrusana Kearfott (Lepidoptera: Tortricidae), a mezclas de acido acetico con fenilacetonitrilo. Curiosamente, las trampas cebadas con fenilacetonitrilo y acido acetico capturaron significativamente mas machos, hembras y polillas totales que el numero de machos atrapados en trampas provistas de un cebo comercial de feromonas sexuales. Demostrandose que la tasa de evaporacion del co-atractante de acido acetico era un factor importante que afectaba las capturas de P. pyrusana con fenilacetonitrilo. La adicion de fenilacetonitrilo a las trampas cebadas con ester de pera, etil (E, Z) -2,4- decadienoato y acido acetico redujo significativamente tanto la captura total como la de hembras de polilla de la manzana, Cydiapomonella (L.) (Lepidoptera: Tortricidae). Sin embargo, ni la captura de C. pomonella ni la de P. pyrusana se vieron afectadas cuando se anadieron fenilacetonitrilo y acido acetico a las trampas cebadas con ester de pera y (E, E)-8,10-dodecadien-1-ol, feromona sexual de polilla de la manzana. Estos resultados respaldan nuestro trabajo mas amplio para desarrollar cebos que mejoren el monitoreo y manejo de varias especies de plagas de la familia Torticididae, que atacan cultivos horticolas en todo el mundo.View this article in BioOne

BACKGROUND Endemic New Zealand grass grub Costelytra zealandica is a pest of introduced pasture that uses phenol as a sex pheromone. The pheromone could be used to monitor and manage grass grub populations, but the irritating properties and toxicity of phenol for human handlers, as well as the possible ecotoxicological effects, pose obstacles to the deployment of the pheromone. This study aimed to limit the use of phenol by dose-response studies and investigation into alternative attractants and synergists to phenol. RESULTS No difference in trap catch was seen across the range of 1-100 mg of phenol, while rates below this (0.001-0.1 mg) caused a large drop in catches. Our results indicated that 1 mg loading in lures was enough to indicate beetle presence over 1 week. 4-Hydroxybenzaldehyde and p-cresol proved unattractive in this study, both as single attractants and as synergists with phenol. Phenyl acetate, phenyl benzoate and diphenyl carbonate all formed phenol under hydrolytic conditions to act as successful propheromones, while phenyl acetate was found to be as attractive as phenol on its own. CONCLUSION This study described several ways to reduce or avoid the use of phenol in the field while maintaining lure effectiveness. © 2017 Society of Chemical Industry.

Vibrational pest management techniques involve the manipulation of the mating behaviour of the target species. Development of such techniques require a deep understanding of the pair formation process. Two types of bioassays were conducted to determine whether a vibrational disruptive approach could be used for Bactericera cockerelli. First, we conducted trials with either single individuals or pairs of a male and a female to ascertain whether B. cockerelli uses vibrational signals to achieve mating. Second, playback trials were conducted using two different female signals to manipulate the behaviour of males. Signals emitted during the trials were recorded using a laser vibrometer from the surface of a leaf where either single individuals or pairs of B. cockerelli were released. We described the communication phases that led to mating and the associated male and female signals. Pair formation started with a male call followed by a female response, which established a vibrational duet. During the female reply, the male searched for the female without emitting vibrational signals. Mating could be achieved if the male could maintain the female replies and reach her. In the playback trials, two different female playbacks attracted males to the signal source. Furthermore, males stimulated with female playbacks spent more time near the source of the signal than insects in the silent control group. We concluded that the B. cockerelli mating behaviour relies on vibrational signals and is potentially susceptible to vibrational manipulation, thus a future vibrational management technique could be developed to monitor or control this species.

Improvements to current brown marmorated stink bug (BMSB), Halyomorpha halys, surveillance and killing systems are needed to improve detection sensitivity and to reduce pesticide use. Detection of BMSB in New Zealand with traps is reliant on sticky panels with aggregation pheromone, which are low cost but inefficient compared with beating foliage. Trapping for BMSB adults and nymphs was conducted daily with lethal traps consisting of an aggregation pheromone-baited-coat hanger covered with dark-colored long-lasting insecticide-treated mesh, we termed &ldquo, The Nazgȗl&rdquo, based on its sinister appearance. A deep tray lined with white plastic was attached centrally at the base for collecting the dead BMSB. The lethal traps killed and caught up to 3.5-fold more nymphs and adult BMSB than identically-baited sticky panels in the 3 weeks of deployment, and provided a snapshot of phenology by instar. We expect that lure-and-kill stations could contribute to the suppression of a delimited population and could be included as part of a semiochemical-based eradication program. Attracting and killing females and nymphs, thus removing future offspring, could contribute to population suppression during an eradication.

The sterility of eggs and nymphs from gamma-irradiated male Halyomorpha halys was investigated to determine the potential for the sterile insect technique (SIT). Males irradiated at 0, 16, 24 and 32 Gy were placed with untreated virgin females, and egg sterility was determined, showing 54.3% at 16 Gy. The percentage of sterility from irradiation was 26 percent lower than previous results from the USA and the variance was very high. Competitive overflooding ratio trials between irradiated virgin males and fertile virgin males at a 5:1 ratio resulted in the expected egg sterility, indicating competitive performance by irradiated males. By July and August, older, irradiated overwintered males were significantly less competitive than similar, non-irradiated males. There is a need to revisit the irradiation delivery method to achieve proper precision around the paternal dose required for an expected &gt, 80% egg sterility and subsequent ~99% endpoint sterility estimated at adult emergence in the F1 phase. These results suggest that the mating competitiveness and competency of males after irradiation at 16 Gy is not limiting to the sterile insect technique for suppression. A wild harvest of overwintering males using the aggregation pheromone, followed by irradiation and male release, might replace rearing. Mass-collected, sterilized bugs could be transported from an area of high H. halys density and shipped for release to enable suppression or eradication elsewhere. This concept is under development but further work is needed now to understand the difference in results between the US and Italian irradiators and increase the reliability of dosimetry.

New, more socially-acceptable technologies are being developed to suppress horticultural pests, because suppression is technically difficult with current technologies, especially in urban areas. One technique involves the release of sterile insects to prevent offspring in the next generation. This technology involves aerial or ground release systems, but this could also create issues for the public. This study investigated community perceptions of a recently-introduced response to codling moth control in New Zealand&mdash, Sterile Insect Technique (SIT). Community attitudes to SIT were examined in Hastings, New Zealand, in April, 2018. Eighty-six detailed interviews were undertaken with a random sample of households. This community was very willing (98% agreement) to host a sex pheromone trap in their gardens, and condoned regular visits to monitor traps. Attitudes to SIT were very positive (98% in favor). Once explained, the concept of using unmanned aerial vehicles to deliver sterile insects was also acceptable (98%) to the community. Use of unmanned aerial vehicles to release sterile insects during a hypothetical incursion response of an exotic fruit fly was also supported at 98% by respondent householders. Investigation of community attitudes can be valuable to guide practitioners in determining suitable technologies before an area-wide programme is launched.

Surveillance for detection of the brown marmorated stink bug, Halyomorpha halys, is reliant on sticky panels with aggregation pheromone, which are low cost, but very inefficient (est. 3%). Trapping for adults was conducted in Italy with novel live (or lethal) traps consisting of aggregation pheromone-baited cylinders with a wind vane, with the upwind end covered by mesh and the downwind end sealed by a removable entry-only mesh cone, admitting the attracted bugs. The novel traps caught up to 15-times more adult H. halys than identically-baited sticky panels in two weeks of daily checking (n = 6 replicates) (the new live traps were, in Run 1, 5-, 9-, 15-, 13-, 4-, 12-, 2-fold, and in Run 2, 7-, 1-, 3-, 7-, 6-, 6-, and 5-fold better than sticky traps, daily). The maximum catch of the new traps was 96 live adults in one trap in 24 h and the average improvement was ~7-fold compared with sticky panels. The rotating live traps, which exploit a mesh funnel facing the plume downwind that proved useful for collecting adults, could also be used to kill bugs. We expect that commercially-available traps could replace the crude prototypes we constructed quickly from local materials, at low cost, as long as the principles of a suitable plume structure were observed, as we discuss. The traps could be useful for the sterile insect technique, supporting rearing colonies, or to kill bugs.

The citrophilous mealybug Pseudococcus calceolariae (Maskell) (Hemiptera, Pseudococcidae) is a primary pest of various crops, including grapevines. The use of insecticides against this species is difficult in most cases because its life cycle includes an extended duration of eggs, juveniles, and adults under the bark and on the roots. Pheromone-based control strategies can present new eco-friendly opportunities to manage this species, as in the case of Planococcus ficus (Signoret) and Planococcus citri (Risso). With this aim it is critical to understand behavioral aspects that may influence pheromone-based control strategies. Herein, the capability of males to fertilize multiple females was investigated, trying to understand whether this behavior could negatively impact the efficacy of mass trapping, mating disruption, or the lure and kill technique. Results showed that a P. calceolariae male can successfully mate and fertilize up to 13 females. The copulation time in subsequent mating events and the time between copulations did not change over time but the number of matings per day significantly decreased. In a further experiment, we investigated the mate location strategy of P. calceolariae males, testing the attractiveness of different loadings of sex pheromone on males in a flight tunnel. Males constantly exposed to 16 rubber septa loaded with the sex pheromone showed a significant decrease in female detection at 1 and 30 &mu, g loadings (0.18 and 0.74 visits per female for each visit per septum, respectively), whereas in the control about 9.2-fold more of the released males successfully detected the female in the center of the array of 16 septa without pheromone. Male location of females in the control (45%) was significantly higher than in the arrays with surrounding pheromone (5% and 20% at 1 and 30 &mu, g loadings, respectively). Mating only occurred in the control arrays (45%). This study represents a useful first step to developing pheromone-based strategies for the control of citrophilous mealybugs.

Detection of pest infestations in fresh produce traded internationally could offer improved prospects for reducing the movement of unwanted pests. Because immature stages of some pests can be difficult to find visually, other cues such as herbivore-induced volatiles that can potentially be detected at the early stages of infestation are worth investigating. In this study, we artificially infested postharvested apples (Malus × domestica ‘Royal Gala’) with two economic apple pests, the specialist codling moth (CM, Cydia pomonella Linnaeus, Lepidoptera: Tortricidae) and the generalist Queensland fruit fly (QFF, Bactrocera tryoni, Froggatt, Diptera: Tephritidae) and collected volatile organic compounds (VOCs) over time (days 0, 6, and 14–15). In both infestation experiments, we found a strong and significant interaction between time and treatment. Apples infested with the QFF emitted lower total amounts of VOCs than uninfested apples, whereas apples infested with the CM released similar total amounts of VOCs. Apples infested with CM had increases in several hexyl and butyl esters, which were particularly noticeable after 15 d. In contrast, changes in ethyl esters were characteristics of QFF infestation and could be detected from day 6. Our multilevel and multivariate statistical analysis identified specific volatile biomarkers for each species at each sampling time that can be used to design a new tool for remote detection and surveillance of these invasive pests in harvested apples. Nevertheless, other information such as the cultivar as well as the storage condition needs to be taken into consideration to increase accuracy of future odorant-based sensors for pest identification.

The composition of the rectal gland secretion and volatiles emitted by female Queensland fruit fly, Bactrocera tryoni was investigated. Esters were found to be the main compounds in the gland extracts and headspace, while amides were the minor compounds in the gland extracts and headspace. Ethyl dodecanoate, ethyl tetradecanoate, ethyl (Z9)-hexadecenoate and ethyl palmitate were the main esters in the gland extracts, while ethyl dodecanoate and ethyl tetradecanoate were the main esters in the headspace. Four amides (N-(3-methylbutyl)acetamide), N-(2-methylbutyl)propanamide, N-(3-methylbutyl)propanamide, and N-(3-methylbutyl)-2-methylpropanamide were found in the gland extracts and the headspace. Among the amides, N-(3-methylbutyl)acetamide and N-(3-methylbutyl)propanamide were the main amides in the gland extracts and the headspace. Traces of three spiroacetals were found both in the gland extracts and in the headspace. (E,E)-2,8-Dimethyl-1,7-dioxaspiro[5.5]undecane, (E,E)-2-ethyl-8-methyl-1,7-dioxaspiro[5.5]undecane, (E,E)-2-propyl-8-methyl-1,7-dioxaspiro[5.5]undecane. All compounds found in the headspace were present in the extract of the rectal gland suggesting that the rectal gland is the main source of the headspace volatiles, whose function remains to be elucidated. This is the first comprehensive chemical analysis of the rectal gland secretions and volatiles of female B. tryoni, and further laboratory and field bioassays are required to determine the function of compounds identified in this study. Discovery of the same amides previously identified in the male rectal gland in the female rectal gland raises questions about the pheromonal role previously suggested for these compounds.

In this study we identified a number of moth (Lepidoptera) species that are potential targets for the sterile insect technique (SIT), and we assessed the feasibility of using stable isotope signatures as markers to distinguish mass-reared from wild moth species. Large natural differences in the isotopic signatures of commercially available sugars render them novel markers for mass-reared insects. Sugar beet (Beta vulgaris L.; Caryophyllales: Amaranthaceae), a C3 plant, has a stable isotopic signature (a measure of the ratio of the stable isotopes 13C:12C) of around −27‰ relative to Vienna Pee Dee Belemnite (VPDB; the international C isotope standard for the stable isotopes, 13C and 12C), and sugarcane (Saccharum spp.; Poales: Poaceae), a C4 plant, has an isotopic signature of around −11‰. Thus by means of such a distinct isotope ratio in the sugar in the diet, mass-reared insects can be easily distinguished from wild insects with a high degree of certainty. It was shown that the method could be extended using a multiple isotope approach, with 15N or a full suite of C, N, S and O isotopes. Intrinsic isotope marking of mass-reared moths proved to be an accurate means of distinguishing wild from mass-reared populations, based on isotopic differences between the wild host plant species and the diets used in mass-rearing, which where possible, had been manipulated to contain the isotopically divergent sugar type. This intrinsic labeling using stable isotopes could be useful in the assessment of the quality of mass-reared moths, because a stable isotope is a marker that does not affect the insect in any detrimental manner. ResumenEn este estudio se identificaron una serie de especies de polillas (Lepidoptera) como objetivos potenciales para la tecnica del insecto esteril (TIE), y se evaluo la viabilidad del uso de firmas isotopicas estables como marcadores para distinguir especies de polillas salvajes de las polillas criadas en masa. Las diferencias naturales mayores en las firmas isotopicas de los azucares comerciales disponibles los hacen nuevos marcadores para los insectos criados en masa. La remolacha azucarera (Beta vulgaris L .; Caryophyllales: Amaranthaceae), una planta C3, tiene una firma isotopica estable (una medida de la proporcion de los isotopos estables: 13C:12C) de alrededor de −27 ‰ relativa a Viena Pee Dee Belemnite (VPDB; el estandar internacional para el isotopo C de los isotopos estables, 13C y 12C), y la cana de azucar (Saccharum spp .; Poales: Poaceae), una planta C4, que tiene una firma isotopica de alrededor de −11 ‰. Por lo tanto, por medio de esta relacion de isotopos distinta en el azucar en la dieta, los insectos criados en masa se pueden distinguir facilmente de los insectos salvajes con un alto grado de certeza. Se demostro que el metodo podria ampliarse mediante un enfoque multiple de isotopos, con 15N o un grupo completo de isotopos C, N, S y O. El marcado de los isotopos intrinsecos de las polillas criadas en masa demostro ser un medio preciso para distinguir entre las poblaciones salvajes y las poblaciones criadas en masa, basado en las diferencias isotopicas entre las especies de plantas hospederas silvestres y de las dietas usadas en la cria en masa, que cuando sea posible, habian sido manipuladas para contener el tipo de azucar isotopicamente divergente. Este marcador intrinseco utilizando isotopos estables podria ser util en la evaluacion de la calidad de las polillas criadas en masa, porque un isotopo estable es un marcador que no afecta el insecto de cualquier manera perjudicial. View this article in BioOne

Irradiation is used to provide sterile insects from mass-rearing facilities, but irradiation can degrade insect quality. A system is described that uses repeatable pheromone stimuli to activate male moths housed with clean airflow in a commercially available insect activity meter, for potential use in quality assessment of mass-reared moths in sterile insect programs. We tested sexually mature wild and sterile light brown apple moth (LBAM), Epiphyas postvittana (Walker) (Lepidoptera: Tortricidae), males at the commencement of scotophase in a simple assay for increased mate-seeking activity after a 2 s stimulus with a 4-component synthetic pheromone source for 2 s, after a 5 s baseline of activity. Male activity at the upwind end of the glass tube was assessed by infrared beam. Next, we tested if a temperature shock at 30 °C in the pupal stage for various durations (0, 1, 2 or 4 h) would have an effect on male moth response to the sex pheromone. The results indicated similar baseline activity in c...

Eradication is the deliberate elimination of a species from an area. Given that international quarantine measures can never be 100% effective, surveillance for newly arrived populations of nonnative species coupled with their eradication represents an important strategy for excluding potentially damaging insect species. Historically, eradication efforts have not always been successful and have sometimes been met with public opposition. But new developments in our understanding of the dynamics of low-density populations, the availability of highly effective treatment tactics, and bioeconomic analyses of eradication strategies offer new opportunities for developing more effective surveillance and eradication programs. A key component that connects these new developments is the harnessing of Allee effects, which naturally promote localized species extinction. Here we review these developments and suggest how research might enhance eradication strategies.

Codling moth was introduced into New Zealand, and remains a critical pest for the apple industry. Apples exported to some markets require strict phytosanitary measures to eliminate the risk of larval infestation. Mating disruption and insecticide applications are the principal means of suppression in New Zealand. We tested the potential for the sterile insect technique (SIT) to supplement these measures to achieve local eradication or suppression of this pest. SIT was trialed in an isolated group of six integrated fruit production (IFP) orchards and one organic orchard (total 391 ha), using sterilized insects imported from Canada, with release by unmanned aerial vehicle and from the ground. Eradication was not achieved across the region, but a very high level of codling moth suppression was achieved at individual orchards after the introduction of sterile moths in combination with mating disruption and larvicides. After six years of releases, catches of wild codling moths at three IFP orchards (224 ha) were 90&ndash, 99% lower than in 2013&ndash, 2014, the year before releases began. Catches at three other IFP orchards (129 ha) decreased by 67&ndash, 97% from the year before releases began (2015&ndash, 2016), from lower initial levels. At a certified organic orchard with a higher initial population under only organic larvicides and mating disruption, by 2019&ndash, 2020, there was an 81% reduction in wild moths capture from 2016&ndash, 2017, the year before releases began.

Nezara viridula Linnaeus (Hemiptera: Pentatomidae) is a polyphagous pest of a wide range of economically important crops. Because the control of this species and other pentatomids relies primarily on insecticide application, investigation into the Sterile Insect Technique (SIT) is warranted. We aimed to investigate the irradiation biology of N. viridula for the potential application of SIT against this pest. Male and female N. viridula were gamma-irradiated at doses between 4 and 28 Gy and mated with both irradiated and nonirradiated conspecifics. Sterility of the resulting eggs followed a dose-response in each case. Irradiated males crossed with untreated females showed higher F1 egg sterility than crosses where the female was irradiated. The greatest F1 egg sterility was observed when both parents were irradiated. There was no obvious dose-response for the longevity of irradiated males, and for the fecundity of nonirradiated females mated with irradiated males. The fecundity of irradiated females appeared to decrease with irradiation dose. These results can be applied to a potential future application of SIT against N. viridula, but predominantly supports the ongoing development of SIT for Halyomorpha halys St&aring, l (Hemiptera: Pentatomidae) and hemipteran pests in general.

Behaviours of insects can be manipulated by transmitting vibrational signals to host plants in order to develop pest management techniques. Bactericera cockerelli is an important pest and uses vibrations for mate-finding. In order to design a future control strategy for B. cockerelli, three different bioassays were performed to assess whether vibrational signals could affect relevant behaviours. Single males or pairs were treated with a female playback in test 1 and 2, respectively. In test 3, mixed sex groups received either different disturbance playbacks. The use of a female playback significantly reduced the mating success of males, since they were attracted towards the source of the stimulus. Moreover, test 2 revealed that B. cockerelli females are competitive, since they used their signals to cover the playback and to duet with males, while in test 3, the disturbance playback, consisting of broadband noises significantly reduced male signalling activity. However, none of the treatments of test 3 negatively affected the mating success of males, which tended to mount the other conspecifics present on the same leaf. The role of vibrations in sexual communication and their potential application as control technique for B. cockerelli are discussed as well.

Codling moth, Cydia pomonella (Lepidoptera: Tortricidae), is a phytosanitary pest of New Zealand&rsquo, s export apples. The sterile insect technique supplements other controls in an eradication attempt at an isolated group of orchards in Hawke&rsquo, s Bay, New Zealand. There has been no attempt in New Zealand to characterize potential sources of uncontrolled peri-urban populations, which we predicted to be larger than in managed orchards. We installed 200 pheromone traps across Hastings city, which averaged 0.32 moths/trap/week. We also mapped host trees around the pilot eradication orchards and installed 28 traps in rural Ongaonga, which averaged 0.59 moths/trap/week. In Hastings, traps in host trees caught significantly more males than traps in non-host trees, and spatial interpolation showed evidence of spatial clustering. Traps in orchards operating the most stringent codling moth management averaged half the catch rate of Hastings peri-urban traps. Orchards with less rigorous moth control had a 5-fold higher trap catch rate. We conclude that peri-urban populations are significant and ubiquitous, and that special measures to reduce pest prevalence are needed to achieve area-wide suppression and reduce the risk of immigration into export orchards. Because the location of all host trees in Hastings is not known, it could be more cost-effectively assumed that hosts are ubiquitous across the city and the area treated accordingly.

Flowers have complex odours often comprising hundreds of volatile compounds. Floral scents are species-specific, and vary also among populations, varieties, sexes or lines, as well as with phenology. Honey bees, Apis mellifera, generally associate only a few key compounds among the complex floral scent with the food reward which guides their foraging choices. How these key compounds are selected remains partially unexplained, despite their crucial role in influencing foraging. Using electrophysiological techniques and behavioural assays, we identified the key bioactive compounds that bees detected with their antennae and that were associated with appetitive responses from four fruit crops and three vegetable crops. Three quantities of identified key volatile compounds were assayed with the two methods in each of four different seasons with experienced foragers. Whether the selection of these key compounds is determined by the sensory capability of the bee or influenced by its foraging experience was assessed by comparing experienced and naïve bees. Our results showed that experienced foragers were electrophysiologically-sensitive to a specific set of key compounds for each crop, independent of variation in quantity among several varieties. Experienced foragers responded to these compounds in all seasons, with increased electrophysiological amplitude with increasing quantities. Behavioural appetitive responses varied amongst compounds and seasons, revealing preferences based on associative learning. Naïve bees that were exposed to compounds and subsequently learned them, tended to be overall more sensitive. We discuss our results based on the identity of each bioactive compound and their presence in nature. Preferences for specific floral compounds based on sensory biases exist and associative learning may reinforce behavioural attraction depending on foraging experience in each season.

The sterile insect technique (SIT) is increasingly being evaluated as a potential complementary strategy for pest suppression or elimination New Zealands export fruit sector has an imperative to meet strict international phytosanitary requirements together with increasing market demand for residuefree produce SIT is a pestspecific method of insect control that can complement current Integrated Pest Management (IPM) strategies Successful SIT presents significant challenges the target pest must be a good candidate for suppression and strong stakeholder and community commitment is required to achieve and maintain suppression until areawide elimination is achieved Emerging sterilisation technologies and refinement of existing methods are making this technology progressively more efficient and costeffective This study reviewed the advantages of including SIT in an IPM programme and described the first use of codling moth SIT in New Zealand A pilot programme is currently underway to evaluate its potential to achieve local elimination of codling moth in Central Hawkes Bay apple orchards

Climate change will alter the threats presented by invasive species. Increasing temperatures and changing precipitation regimes will likely simultaneously improve the suitability of a region for some species while decreasing it for others. We demonstrate the zero-sum game nature of these changes by modelling the changes to the projected distribution of 13 tropical and subtropical Tephritidae species in cities in Australia and New Zealand using published CLIMEX models. Under current climate conditions, tropical and warm temperate cities were suitable for more species than arid or cool temperate ones. All New Zealand cities increased in suitability, while Australian cities show more variable responses. The changes that occur under climate change are in line with the expectation of species ranges moving into higher latitudes but are also influenced by changes to the precipitation regime. With climate change, the nature of biosecurity threats will alter, the range of species able to survive in cool temperate regions is likely to increase with decreases in species ability to survive in tropical regions. Biosecurity agencies will need to respond to changing geography of threats.

We studied the variability and plasticity of individual aggressiveness in a social insect, describing and quantifying the sting extension response (SER) of the common wasp Vespula vulgaris. As a proxy for individual aggressiveness we measured the SER of individual wasps, scoring the extent by which the sting was extruded in response to a mild electric shock (7.5 or 12 V for 2 s) on a scale from 0 to 1. We found that wasps vary greatly in their stinging propensity and aggression thresholds and that individuals change their SER during their life. Extremely aggressive or docile phenotypes, showing at first consistent mutual differences on different days, tended to converge over time and developed comparable SER responses later in their life. Older individuals tended to be more aggressive. Wasp size was not related to the stinging phenotype. Wasp foragers had a less pronounced sting extension than individuals previously involved in nest defense. For the same individual, the aggressive response was proportional to the intensity of the negative stimulus. We discuss the advantages of the SER bioassay as a tool to measure individual aggressiveness, plasticity and inter-individual variability in the Aculeata group, and its great potential in comparative and learning studies.

Phytophagous insects detect volatile compounds produced by host and non-host plants, using species-specific sets of olfactory receptor neurons (ORNs). To investigate the relationship between the range of host plants and the profile of ORNs, single sensillum recordings were carried out to identify ORNs and corresponding active compounds in female Uraba lugens (Lepidoptera: Nolidae), an oligophagous eucalypt feeder. Based on the response profiles to 39 plant volatile compounds, 13 classes of sensilla containing 40 classes of ORNs were identified in female U. lugens. More than 95% (163 out of 171) of these sensilla contained 16 classes of ORNs with narrow response spectra, and 62.6% (107 out of 171) 18 classes of ORNs with broad response spectra. Among the specialized ORNs, seven classes of ORNs exhibited high specificity to 1,8-cineole, (±)-citronellal, myrcene, (±)-linalool and (E)-β-caryophyllene, major volatiles produced by eucalypts, while nine other classes of ORNs showed highly specialized responses to green leaf volatiles, germacrene D, (E)-β-farnesene and geranyl acetate that are not produced by most eucalypts. We hypothesize that female U. lugens can recognize their host plants by detecting key host volatile compounds, using a set of ORNs tuned to host volatiles, and discriminate them from non-host plants using another set of ORNs specialized for non-host volatiles. The ORNs with broad response spectra may enhance the discrimination between host and non-host plants by adding moderately selective sensitivity. Based on our finding, it is suggested that phytophagous insects use the combinational input from both host-specific and non-host specific ORNs for locating their host plants, and the electrophysiological characterization of ORN profiles would be useful in predicting the range of host plants in phytophagous insects.

BACKGROUND Invasive ants, such as the Argentine ant, have often been reported to facilitate honeydew-producing hemipteran pests such as mealybugs, which can be vectors of plant pathogens. Synthetic pheromones may offer a target-specific method to control such ants and consequently lower the abundance of honeydew-producing pests. Here we report the results of a trial to suppress Argentine ants in grapevines using ant pheromone dispensers. RESULTS Compared with untreated controls, we observed a significant drop in Argentine ant activity on the ground, irrespective of whether pheromone dispensers were placed at ground level, within the canopy or in both locations. Ant counts in the canopy confirmed that Argentine ant abundance was reduced under the influence of the pheromone dispenser placed at ground level compared with untreated controls. However, placing dispensers only in the canopy did not reduce the numbers of ants within the canopy compared with untreated controls. CONCLUSION Our results showed that pheromone dispensers can significantly reduce Argentine ant foraging in grapevines if they are positioned appropriately. This technique could potentially reduce the abundance of associated mealybugs and potentially attendant virus vectoring areawide. © 2015 Society of Chemical Industry

Eradication technologies are needed for urban and suburban situations, but may require different technologies from pest management in agriculture. We investigated mating disruption of a model moth species recently targeted for eradication in Californian cities, by applying dollops of SPLAT releasing a two-component sex pheromone of the light brown apple moth in 2-ha plots in low-density residential Perth, Australia. The pheromone technology was applied manually at ∼1.5 m height to street and garden trees, scrubs, and walls at 500 dollops per hectare of 0.8 g containing ∼80 mg active two-component pheromone. Catches of male moths were similar among all plots before treatment, but in treated areas (six replicates) pheromone trap catches were substantially reduced for up to 29 wk posttreatment, compared with untreated control plot catches (three replicates). The treatment with pheromone reduced catch to virgin females by 86% (P

The apparent absence of intra-nest signals and communication about food resources (recruitment) among social wasps does not rule out the possibility of information transfer and coordinated foraging among nestmates. In the present study, we tested the hypothesis that the common wasp (Vespula vulgaris) shows nest-based information transfer and foraging activation: an increase in the probability of an individual leaving the nest as a result of information about resources received from successful foragers. We controlled for the possibility of local enhancement, chemical trails at the food source and climatic variation. We found evidence that food choice and discovery of resources in the field by naive foragers were assisted by information previously or simultaneously provided by experienced nestmates. This information was related to chemical cues associated with the food and possibly to its location. Our observations suggest piloting between common wasp foragers. At the trained nest, there was a change in foraging effort at the colony level when known resources were available. Reactivated, experienced foragers were the main group responsible for the increase in foraging traffic rate observed at the colony level. To our knowledge, this is the first study clearly demonstrating nest-based information transfer about food resources in V. vulgaris and one of the few providing evidence of foraging activation in social wasps. Our data are consistent with the possibility of recruitment in this group of social insects.

BACKGROUND The identification of new attractants can present opportunities for developing mass trapping, but standard screening methods are needed to expedite this. We have developed a simple approach based on quantifying trap interference in 4 × 4 trap arrays with different spacings. We discuss results from sex pheromones in Lepidoptera (light brown apple moth, Epiphyas postvittana), Diptera (apple leaf curling midge, Dasineura mali) and Homoptera (citrophilous mealybug, Pseudococcus calceolariae), compared with a kairomone for New Zealand flower thrips (Thrips obscuratus). RESULTS The ratio of catch in corner traps to catch in centre traps was 25:1 at 750 D. mali traps ha−1, and was still ∼5:1 at 16 traps ha−1, suggesting trap interference even at such low trap densities. Trap competition for sex pheromone lures at close spacing (

BACKGROUND: The number of insect eradication programmes is rising in response to globalisation. A database of arthropod and plant pathogen eradications covers 1050 incursion responses, with 928 eradication programmes on 299 pest and disease taxa in 104 countries (global eradication database b3.net.nz/gerda). METHODS: A subset of the database was assembled with 211 eradication or response programmes against 17 species of fruit flies (Tephritidae) in 31 countries, in order to investigate factors affecting the outcome. RESULTS: The failure rate for fruit fly eradication programmes was about 7%, with 0% for Ceratitis capitata (n = 85 programmes) and 0% for two Anastrepha species (n = 12 programmes), but 12% for 13 Bactrocera species (n = 108 programmes). A number of intended eradication programmes against long-established populations were not initiated because of cost and other considerations, or evolved during the planning phase into suppression programmes. Cost was dependent on area, ranged from $US 0.1 million to $US 240 million and averaged about $US 12 million (normalised to $US in 2012). In addition to the routine use of surveillance networks, quarantine and fruit destruction, the key tactics used in eradication programmes were male annihilation, protein bait sprays (which can attract both sexes), fruit destruction and the sterile insect technique. CONCLUSIONS: Eradication success generally required the combination of several tactics applied on an area-wide basis. Because the likelihood of eradication declines with an increase in the area infested, it pays to invest in effective surveillance networks that allow early detection and delimitation while invading populations are small, thereby greatly favouring eradication success. © 2014 Society of Chemical Industry Supporting information may be found in the online version of this article.

BACKGROUND New Zealand flower thrips (NZFT), Thrips obscuratus (Crawford), is an economic pest of various horticultural crops in New Zealand and is recognised as a quarantine pest globally. Two chemical attractants (ethyl nicotinate and 6-pentyl-2H-pyran-2-one), three dispensers, three trap designs and four trap heights were investigated to determine the most effective method for monitoring NZFT. Phenology of NZFT at two locations was compared. RESULTS 6-Pentyl-2H-pyran-2-one in a polyethylene bag dispenser was the most attractive lure formulation and exhibited high stability in release rate trials. There was no difference in NZFT catch between vertical-panel and cross-panel traps, but both caught significantly more than delta traps. However, both types of panel trap had unacceptably high by-catch of native insects. Catch of thrips increased with height from 0 to 3 m. Phenology of NZFT showed similar population trends at both locations, but with a timing difference of around 50 days. CONCLUSIONS Delta traps containing 6-pentyl-2H-pyran-2-one in a polyethylene bag at 2 m above the ground is the recommended method for monitoring NZFT, significantly improving the sensitivity, accuracy and labour input compared with prior methods. Long-term monitoring of NZFT could lead to more accurate economic damage thresholds and timing for when to apply insecticides. © 2014 Society of Chemical Industry

The introduction of invasive social wasp species of the genus Vespula (Hymenoptera: Vespidae) to New Zealand has caused a major ecological problem, particularly in the beech forests (Nothofagus spp.) of the South Island, where they have destabilized the native bird and invertebrate biodiversity. New attractants are under investigation as part of a search for pest management solutions. Fermenting brown sugar has been previously reported as a social wasp attractant. This work was undertaken to identify compounds from fermented brown sugar attractive to social wasps. Raw fermented brown sugar was confirmed to be attractive in a field trial and 10 chemical compounds present in the headspace were positively identified by coupled gas chromatography-mass spectrometry and synthetic references. During electroantennogram experiments, 3-methyl-1-butanol, 3-methylbutyl acetate, and ethyl hexanoate elicited high electrophysiological responses from Vespula vulgaris (L.) antennae. These compounds mediated attraction of V. vulgaris wasps in forest margins by trapping. A blend of these compounds could be used as a lure in a monitoring tool, or even a local suppression method if combined with a toxin.

Research to discover and develop attractants for the codling moth, Cydia pomonella L., has involved identification of the chemicals eliciting moth orientation to conspecific female moths, host fruits, fermented baits, and species of microbes. Pear ester, acetic acid, and N-butyl sulfide are among those chemicals reported to attract or enhance attractiveness to codling moth. We evaluated the trapping of codling moth with N-butyl sulfide alone and in combination with acetic acid and pear ester in apple orchards. Acetic acid was attractive in two tests and N-butyl sulfide was attractive in one of two tests. N-Butyl sulfide increased catches of codling moth when used with acetic acid to bait traps. N-Butyl sulfide also increased catches of codling moth when added to traps baited with the combination of acetic acid and pear ester. Male and female codling moth both responded to these chemicals and chemical combinations. These results provide a new three-component lure comprising N-butyl sulfide, acetic acid, and pear ester that is stronger for luring codling moth females than other attractants tested.

This medal is awarded by the New Zealand Plant Protection Society to honour those who have made exceptional contributions to plant protection in New Zealand in the widest sense. The medal is awarded for outstanding services to plant protection, whether through research, education, implementation or leadership. In 2017, the New Zealand Plant Protection Medal was awarded Prof David Maxwell (Max) Suckling. In his 35+ years of research, Max has been pivotal in bringing odour-based technologies to New Zealand. In particular, his research on insect pheromones has enabled integrated pest management to be realised in this country. As a result, New Zealand plant-based industries can access premium overseas markets due to the low pest prevalence and low pesticide residue on primary produce. It has also reduced grower exposure to pesticides. The acknowledgement of his broad knowledge of risks and benefits that new organisms and substances can pose to New Zealand has been exemplified by his position of Chair of the Environmental Risk Management Authority Hazardous Substances and New Organisms Committee where he presided over decisions from determining which organisms are new to New Zealand through to whether the benefits of the release of new organisms outweighed the risks. His unique knowledge and ability to make sound judgements based on the evidence presented also led to two invitations back to the Environmental Protection Authority after he had finished as a special member on the Committee so that New Zealand could safely continue to assess the use of biological control agents. Since 2004, in his role as Science Group Leader of the Biosecurity group at The New Zealand Institute for Plant and Food Research Ltd (PFR), Max has been instrumental in developing tools to improve detection sensitivity and socially acceptable eradication options for new pests that threaten New Zealand, such as the Queensland fruit fly and the painted apple moth. Max has been a member of the New Zealand Plant Protection Society for many years and served as President from 1999 to 2001. He was nominated for the Medal because of the passion he has displayed towards developing and making available socially acceptable pest eradication and management tools in New Zealand. The work that he and the chemical ecology team he has built and led, has had a large impact in many sectors from horticulture to biosecurity. This use of socially acceptable tools for the productive sectors naturally led to Max’s involvement in the pest surveillance and eradication space. He led the Eradication and Response Theme in the Better Border Biosecurity collaboration for over ten years, co-ordinating research among Crown Research Institutes to achieve their goals and the goals of New Zealand’s biosecurity practitioners. He has gone beyond odour-based technologies and branched into sound, vision and sterile-insect technologies for managing pests, sticking with the social acceptance theme. Max is an innovative thinker, testing novel approaches for pest management, and can bring quite separate groups together to achieve a goal. For example, he combined an irradiator used to sterilise medical equipment and insect rearing to achieve a boutique insect-sterilisation programme against the painted apple moth. By pushing the envelope, he is seen as a world leader in his field of using socially acceptable tools, with numerous invitations as a keynote speaker at international meetings, which has allowed him to return to New Zealand with some of the latest scientific ideas. He has served on working groups of the sterile-insect technique for the joint division of the Food and Agriculture Organization/International Atomic Energy Agency. He was recently made a professor when he was made a joint appointment at PFR and the University of Auckland, and has supervised and co-supervised a number of PhD and MSc students. His outstanding collaboration and mentoring skills enable him to work across different fields, secure new knowledge and tools for novel pest-management approaches, bring together people from different organisations, and mentor ‘thinking-out-of-the-square’ scientists for the future. His desire to protect New Zealand’s flora, fauna and people, make him a worthy recipient of the New Zealand Plant Protection Medal. NZPP Medal recipients for the previous five years: 2016: Rob Beresford 2015: Gary Barker 2014: - 2013: Andrew Hodson 2012: Margaret Dick

Two glasshouse trials in a capsicum crop near Warkworth, New Zealand, in January 2011 and two field trials in a nectarine orchard near Lleida, Spain, in July 2013 were undertaken to determine if trap capture of Frankliniella occidentalis (western flower thrips, WFT) and Thrips tabaci (onion thrips, OT) could be increased by alternative volatile compounds beyond the known thrips attractant, methyl isonicotinate (MI). On blue sticky board traps in the crop in New Zealand, none of six alternative compounds tested caught more thrips (mostly WFT, OT and two other species) than the Control traps. In contrast to MI, catches with the alternative lures were mostly significantly lower. For both trials in the orchard in Spain using white water traps, the highest numbers of WFT and OT were caught in traps with MI, significantly higher than the Control (up to 11× for both species) and higher than most of the nine alternative odour compounds tested.

BACKGROUND With growing globalization and trade, insect incursions are increasing worldwide. A proportion of incursions involve pests of major economic crops (e.g. Mediterranean fruit fly), conservation value (e.g. tramp ants) or health significance (e.g. mosquitoes), and may be the targets of eradication programmes. Historically, such responses have included the use of broad-spectrum insecticides. However, with increasing public awareness of the negative aspects of pesticides, new environmentally friendly and effective techniques are needed. Here, we review and evaluate a range of selective to broad-spectrum tactical options for suppression which either have, or show potential for, integration within arthropod eradication programmes. RESULTS Most of the available technologies have their roots in pest management, but higher efficacy is required. Further refinement may be needed for use in eradication. Integration of several tactics is usually needed, as compatible tools can be used simultaneously to target different parts of the pest life cycle. However, not all technologies are fully compatible; for example, the simultaneous use of mass trapping and the sterile insect technique (SIT) may be suboptimal, although sequential application may still be effective. CONCLUSIONS Broad-spectrum insecticides are generally incompatible with some biologically based technologies such as the SIT, but may be used to reduce the population so that density-dependent tactics can be used. Several novel technologies with fewer nontarget impacts have been proposed in recent years, and need to be properly evaluated for their applicability to insect eradication. Overall, there are still major gaps in surveillance and selective eradication technologies for most insects. © 2013 Society of Chemical Industry

A wide known host range in Australia and novel herbivory on native and naturalized species in New Zealand supported the decision to commence a NZ$65 million eradication programme against painted apple moth [Teia anartoides (Walker) (Lepidoptera: Lymantriidae)] in Auckland (1999–2007). Laboratory no-choice tests were designed to examine the ‘host’ status of the associations seen in the field. Laboratory tests investigated 79 native and introduced plant species with 122 provenances. Forty-two percent of plants were capable of supporting larval development to adulthood, with male bias; 30% were defined as potential hosts with female larvae developed through to the pupal stage; > 10% survival indicated probable physiological hosts. Sporadic or more frequent attack of New Zealand native broom, and introduced lemon, apple, sycamore, walnut, cherry and poplar, was likely, with a wider range of hosts supporting male emergence. A few negative laboratory results contradicted field observations of significant damage by large numbers of larvae. The present study highlights the challenge faced with respect to predicting the ecological host range of invasive polyphagous species, whose biology is little known, during the early stages of a first invasion. The implications of a wider host range found in males than females are discussed.

The sterile insect technique (SIT) potentially provides a socially acceptable approach for insect eradication of new pest incursions. The light brown apple moth, Epiphyas postvittana (Walker) (Lepidoptera: Tortricidae), was discovered in Berkeley (CA, USA) in 2006, leading to an incursion response that included this technology. In this study, we assessed factors affecting mating success from a bisex release of irradiated moths: effects of radiation dose on male multiple mating, male flight competition, female sex pheromone titre and attractiveness of irradiated females to males, and identification of successful mating in vineyards of either irradiated or wild males (identified by isotope analysis of spermatophores from sentinel females). There was a significant negative relationship between male radiation dose and mating frequency. In head-to-head flights of irradiated males against non-irradiated males to a pheromone lure in a wind tunnel, irradiated males reached the lure first only 31% of the time. With increasing radiation dose, the production of the major sex pheromone component in females, (E)-11-tetradecenyl acetate, dropped, from 0.7 ± 0.1 ng per female in non-irradiated females to 0.2 ± 0.07 ng per female when irradiated at 300 Gy. Male catch was reduced to 11% of control females in traps containing females irradiated at 300 Gy. Isotope analysis of spermatophores found in the bursa copulatrix of females indicated that mating success of irradiated males inside the live (entry-only) traps containing virgin females was lower (13.1 ± 3.3%) than suggested by male catch (21.2 ± 3.8%) in pheromone traps, the current standard for assessing field competitiveness. Impacts of irradiation on male and female moth fitness should be taken into account to improve estimates of irradiated to wild male E. postvittana overflooding ratios needed for population suppression.

Emerging concern highlighting non-target impacts in classical biological control of arthropods and weeds has heightened awareness of these risks but raised the risk of obscuring beneficial effects. This review applied a retrospective assessment of the benefits from weed biological control in New Zealand, using the framework designed for pre-clearance assessment of classical biological control. Of those agents released which can be assessed because of sufficient passage of time (n = 33), their impact has been assessed according to the modern criteria for judging beneficial effects used by New Zealand’s Environmental Protection Authority (negligible, minimal, minor, moderate, major and massive). Cases with negligible benefit (n = 12) included failures to establish self-sustaining populations, while cases with minimal benefit (n = 11) included some where predation reduced the realized benefit of established organisms. The remaining cases offered massive (n = 2), major (n = 1), moderate (n = 5) or minor (n = 2) benefit. Suppression of ragwort (Jacobaea vulgaris Gaertn, 1754), and St. Johns wort (Hypericum perforatum L.) were considered to be massive in magnitude, offering long term ecosystem benefits of controlling invasive weeds. Improved clarity around risk and benefit could help improve the quality of debate on biological control, and the five step scale used in New Zealand may prove more widely useful elsewhere.

Sex attraction studies were carried out to investigate the mate-finding behaviour of invasiveVespula vulgaris(Linnaeus) (Hymenoptera: Vespidae) wasps. Delta traps were baited with live, caged males, and gynes (virgin queens) ofV. vulgaristo determine whether either sex produced a long-range sex attractant. Traps baited with gynes caught 71 males, while the controls and live-male wasp baited traps did not catch gynes. Wind tunnel trials were performed to verify if the signal produced by the gynes was chemical in nature. First,V. vulgarismales were flown to live caged gynes, where more than half of the males tested flew upwind in a zigzagging pattern and made contact with caged gynes. Males were also flown to hexane rinses of gynes and flew upwind in a zigzagging pattern towards the gyne extract, although none made contact with the cotton roll stimulus. The results presented here demonstrate conclusively thatV. vulgarisgynes produce a sex pheromone.

Light brown apple moth [Epiphyas postvittana (Walker)] is now established as an economic and quarantine pest in California, and new technologies are being investigated to increase options for its management. Two new organic formulations for mating disruption, SPLAT LBAM HD-O and organic Hercon Biotie (biodegradable) were field tested at four point source densities (25, 72, 322, and 500/ha) and compared with the standard Isomate LBAM Plus (500/ha, as a positive control) and an untreated (negative) control. Assessment involved trapping using synthetic lures and virgin females. In total, 175,776 male light brown apple moths were caught to both the caged females and synthetic lures, from 10 February to 19 May 2011. The light brown apple moth catch dramatically decreased from baseline measurements after the treatments were applied, with the highest density treatments reducing catch to below 10% of the catch in the untreated controls within the first week (> 90% disruption). In synthetic lure traps, the SPLAT and Biotie treatment performed similarly well over all rates (P = 0.317 for posttreatment percentage communication disruption), but SPLAT performed better at disrupting virgin female traps (P = 0.045). There was a significant increase in disruption with an increasing number of points/ha (P 0.74). Disruption of this species in vineyards is thus highly feasible.