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Crop breeding programmes generally select for traits for improved yield and human consumption preferences. Yet, they often overlook one fundamental trait essential for insect-pollinated crops: pollinator attraction. This is even more critical for hybrid plants that rely on cross-pollination between the male-fertile line and the male-sterile line to set seeds. This study investigated the role of floral odours for honey bee pollination that could explain the poor seed yield in hybrid crops.; Results: The key floral bioactive compounds that honey bees detect were identified for three vegetable hybrid crops. It was found that 30% of the variation in bioactive compound quantities was explained by variety. Differences in quantities of the bioactive compounds triggered different degrees of olfactory response and were also associated with varied appetitive response. Correlating the abundance of each bioactive compound with seed yield, it was found that aldehydes such as nonanal and decanal can have a strong negative influence on seed yield with increasing quantity.; Conclusion: Using these methodologies to identify relevant bioactive compounds associated with honey bee pollination, plant breeding programmes should also consider selecting for floral traits attractive to honey bees to improve crop pollination for enhanced seed yield. © 2018 Society of Chemical Industry.; © 2018 Society of Chemical Industry.

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.

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.

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.

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

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.

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.

BACKGROUND: The fire ant, Solenopsis invicta, is one of the most aggressive and invasive species in the world. The trail pheromoneZ,E-α-farnesene(91%purity)wasprepared,anddisruptionofworkertrailorientationwastestedusinganethanolbasedaerosolformulationpresentingasinglepuffofthiscompoundbyairbrushandcompressedair.Trail-followingbehaviour was recorded by overhead webcam and ants digitised before and after presentation of the aerosol treatment at four rates (1.6, 16, 160 and 1600 ng cm −2 ). RESULTS: Ants preferred 110 ng cm −1 over 11, 1.1 and 0.11 ng cm −1 for trail following. Within seconds of presentation of 1600 ng cm −2 , the highest dose tested, trail disruption was observed. Disruption was evident as reduced arrival success and reduction in the trail integrity statistic (r 2 ), as well as increased deviation from the trail (deg). The distribution of walking track angles was also flattened. CONCLUSIONS: The feasibility of using aerosol for delivery of trail pheromone was demonstrated, but the need for high purity combined with the difficulty of commercial supply makes this technique impractical. However, the commercial production of Z,E-α-farnesene of high purity by industrial biotechnology or from (E)-nerolidol may be possible in future, which would facilitate further development of trail pheromone disruption ofS.invicta. c � 2012 Society of Chemical Industry

BACKGROUND: Pheromones of two native leafrollers of economic importance to the New Zealand horticulture industry, Planotortrix octo [(Z)-8-tetradecenyl acetate and tetradecyl acetate] and Ctenopseustis obliquana [(Z)-5-tetradecenyl acetate and (Z)-8-tetradecenyl acetate], were reinvestigated and combined with pheromone of Epiphyas postvittana [light-brown apple moth, (E)-11-tetradecenyl actetate and (E, E)-9,11-tetradecen-1-yl acetate] to develop a single dispenser for mating disruption of three pest species for integrated pest management. RESULTS: Additional compounds identified from pheromone gland extracts were characterised as repellents for P. octo. However, for C. obliquana from Central Otago, a change in ratio of (Z)-5-tetradecenyl acetate and (Z)-8-tetradecenyl acetate and the addition of three compounds found in the gland (dodecyl acetate, tetradecyl acetate and hexadecanal) led to a significant improvement in catch over previous lures. Males from Central Otago showed antennal electrophysiological responses to hexadecanal, unlike C. obliquana from Auckland, which did not. Three multiple-species disruption blends were devised in a single dispenser to target E. postvittana, P. octo and C. obliquana. Disruption of traps was recorded in single-tree replicates with all three blends, but the five-component blend was overall most effective at disruption and was deployed area wide in commercial orchard plots. CONCLUSIONS: Deployment of single dispensers into commercial stone fruit orchards led to disruption of trapping for the three species and measurable reductions in insecticide use in cherries, peaches and nectarines without increased fruit damage (assessed in apricots). Copyright © 2011 Society of Chemical Industry

BACKGROUND: Public opposition to aerial application of sex pheromone for mating disruption of light-brown apple moth (LBAM), Epiphyas postvittana (Walk.), in California stopped its further use in the ca $ 74 million eradication programme in 2008, underscoring the need for other eradication tactics. It is demonstrated that pheromone-treated sterile Mediterranean fruit flies (medflies), Ceratitis capitata Wied., can disrupt communication in male moths. RESULTS: Medflies topically dosed with moth pheromone (E)-11-tetradecenyl acetate showed a no observed effect level (NOEL) of ∼10 µg fly−1, with increasing toxicity from 30 to 100 µg fly−1. Greater potency and longevity of attraction and lower mortality were achieved using microencapsulated pheromone. Releases of 1000 pheromone-treated medflies ha−1 prevented male moth catch to synthetic lures in treated 4 ha plots for 1 day in suburban Perth, Australia. Releases of ca 3000 pheromone-treated medflies ha−1 disrupted catch to single female moths in delta traps, and to synthetic pheromone lures. Percentage disruption on the first four nights was 95, 91, 82 and 85%. CONCLUSIONS: Disruption of moth catch using pheromone-treated medflies is a novel development that, with future improvement, might provide a socially acceptable approach for application of the insect mating disruption technique to control invasive insects in urban environments. Adequacy of payload and other issues require resolution. Copyright © 2011 Society of Chemical Industry

Lepidoptera are among the most severe pests of food and fibre crops in the world and are mainly controlled using broad spectrum insecticides. This does not lead to environmentally sustainable control and farmers are demanding alternative control tools which are both effective and friendly to the environment. The sterile insect technique (SIT), within an area-wide integrated pest management (AW-IPM) approach, has proven to be a powerful control tactic for the creation of pest-free areas or areas of low pest prevalence. Improving the quality of laboratory-reared moths would increase the efficacy of released sterile moths applied in AW-IPM programmes that integrate the (SIT). Factors that might affect the quality and field performance of released sterile moths are identified and characterized in this study. Some tools and methods to measure, predict and enhance moth quality are described such as tests for moth quality, female moth trapping systems, ‘smart’ traps, machine vision for recording behaviour, marking techniques, and release technologies. Methods of enhancing rearing systems are discussed with a view to selecting and preserving useful genetic traits that improve field

International audience; Modelling moth dispersal in relation to wind direction and strength could greatly enhance the role of pheromone traps in biosecurity and pest management applications. Anemotaxis theory, which describes moth behaviour in the presence of a pheromone plume and is used as a framework for such models. Currently, however, that theory includes only three components: upwind, zigzagging, and sideways casting behaviour. We test anemotaxis theory by analysing the data from a series of mark– release–recapture experiments where the wind direction was known and the insects were trapped using an irregular grid of pheromone traps. The trapping results provide evidence of a downwind component to the flight patterns of the released insects. This active or passive downwind dispersal is likely to be an appetitive behaviour, occurring prior to the elicitation of pheromone-oriented flight patterns (pheromone anemotaxis). Given the potential for significant displacement during down-wind dispersal, this component will have impact on final trap captures and should be considered when constructing moth dispersal models.

BACKGROUND: The common wasp, Vespula vulgaris (L.), and the German wasp, Vespula germanica (F.), are significant problems in New Zealand beech forests (Nothofagus spp.), adversely affecting native ...

Fungi and bacteria on the external surfaces of four gorse-associated insect species: gorse seed weevil Apion ulicis Forster (Coleoptera: Apionidae), light brown apple moth Epiphyas postvittana Walker (Lepidoptera: Tortricidae), gorse pod moth Cydia ulicetana Denis and Schiffermuller (Lepidoptera: Tortricidae) and gorse thrips Sericothrips staphylinus Haliday (Thysanoptera: Thripidae), were recov- ered by washing and plating techniques. The isolates were identified by morphology and polymerase chain reaction (PCR) restriction fragment length polymorphism and sequencing of internally tran- scribed spacer (ITS) and 16S rDNA. A culture-independent technique (direct PCR) was also used to assess fungal diversity by direct amplification of ITS sequences from the washings of the insects. All insect species carried Alternaria, Cladosporium, Corallomycetella, Penicillium, Phoma, Pseudozyma spp. and entomopathogens. Ninety-four per cent of the 178 cloned amplicons had ITS sequence similarity to Nectria mauritiicola (syn. Corallomycetella repens) .E. postvittana carried the largest fungal spores (spore mean surface area of 126 mm 2 ) and the most fungal colony forming units per insect. Methylo- bacterium aquaticum and Pseudomonas lutea were isolated from all four insect species. P. fluorescens was the most abundant bacterium on the lepidopteran insects. This study presents the diversity of microbial taxa on insect exoskeletons, and provides the basis for developing a novel mycoherbicide delivery strategy for biological control of gorse using insects as vectors of a plant pathogen.

BACKGROUND: Fruit flies (Diptera: Tephritidae) represent a major biosecurity threat to the horticulture sector of New Zealand, which is entirely free of these invasive pests. A nationwide surveillance programme is conducted to ensure any incursion is detected as early as possible. A review of the lure dispensers used is reported here. RESULTS: Lure dispenser emission trials found that the currently used lure plugs release lure more slowly under New Zealand subtropical to temperate climates than wafer dispensers. Subsequent trapping experiments at high altitude in Hawaii (as a mimic of New Zealand meteorological and expected fruit fly ecological conditions) compared Lynfield traps baited with the existing lure plug dispensers and newer wafer dispensers. Catches of wild Oriental fruit flies, Bactrocera dorsalis (Hendel), were 9.5-fold higher with methyl eugenol wafers than with the plugs. Recaptures of sterile melon flies, Bactrocera cucurbitae (Coquillet), were 2.6-fold higher with cuelure wafers than with the plugs. Recaptures of sterile Mediterranean fruit flies, Ceratitis capitata Weid., were not significantly higher with trimedlure wafers than with the plugs. CONCLUSIONS: Release rate and trapping experiments found new lure dispensers differed in release rate characteristics from existing dispensers under temperate and subtropical conditions, and indicated some potential for improvement in surveillance efficacy. Copyright © 2008 Society of Chemical Industry

The antennal and behavioural response of three tortricid species (Lepidoptera: Tortricidae) to their corresponding sex pheromones and known or putative behavioural antagonists was tested by electroantennography and in field trials. The species and their pheromones and known or proposed behavioural antagonist were lightbrown apple moth, Epiphyas postvittana (Walker) [pheromone: 95% (E)-11-tetradecenyl acetate (E11-14Ac) and 5% (E,E)-9,11-tetradecadienyl acetate (E9E11-14Ac); antagonist: (Z)-11-tetradecenyl acetate (Z11-14Ac)], codling moth, Cydia pomonella (L.) [pheromone: (E,E)-8,10-dodecadien-1-ol (codlemone); antagonist: (E,E)-8,10-dodecadienyl acetate (codlemone acetate)], and gorse pod moth, Cydia ulicetana (Haworth) [pheromone: (E,E)-8,10-dodecadienyl acetate (codlemone acetate); putative antagonist: (E,E)-8,10-dodecadien-1-ol (codlemone)]. In all three species, the antennal response to the antagonists was not significantly different from the antennal response to con-specific sex pheromone compounds. In the field trapping experiments, significantly fewer males of all three species were attracted to the respective pheromone when blended with the behavioural antagonist compound. However, this response varied between the species, with lightbrown apple moth and codling moth showing stronger responses to the antagonist compounds than gorse pod moth. Both lightbrown apple moth and codling moth males were able to discriminate between pure pheromone and pheromone blended with the antagonist when placed in traps side-by-side separated by ca. 10 cm. The presence of the behavioural antagonist not only affected the catch of males of both species within their own traps but also affected the catch in the neighbouring trap that contained con-specific sex pheromone; the catch of gorse pod moth was not reduced by the presence of codlemone in the neighbouring trap. These results suggest that strong behavioural antagonists such as codlemone acetate for codling moth and Z11-14Ac for lightbrown apple moth induce their inhibition effect at a substantial distance downwind from the odour source; however, most of those males that were able to overcome this inhibition effect at the early stage of orientation to odour source, were able to discriminate between the pheromone source and the pheromone source admixed with behavioural antagonist. Moderate behavioural antagonists such as codlemone for gorse pod moth did not elicit a discrimination effect.

1 The sterile insect technique (SIT) involves the release of large numbers of sterile or partially-sterile insects into a wild pest population to dilute the number of successful wild matings, with the eventual aim of eradication or area-wide suppression. General population models, encompassing a wide range of SIT types, were used to derive principles for optimizing the success of SIT, with particular emphasis on the application of partial sterility leading to inherited sterility in the F1 population. 2 The models show that inherited sterility can only be guaranteed to be more effective than complete sterility if matings between irradiated-lineage partners are unsuccessful. This is widely assumed but rarely examined experimentally. 3 The models allow the critical overflooding ratio, φc, to be calculated for a particular target species, suggesting the release rate required to prevent population increase. Successful eradication using SIT alone should aim for a substantially higher release rate than suggested by φc. 4 The models show that pest populations may continue to increase in the first few generations of SIT releases, regardless of release rate, as irradiated-lineage individuals infiltrate the population. This does not necessarily imply that the SIT programme will be unsuccessful in the longer term. 5For pests with overlapping generations, the models suggest that frequent small releases may be more effective than less frequent large releases, particularly when the average release rate is close to the critical threshold for success.

Fuller's rose weevil (FRW; Pantomorus cervinus) (Coleoptera: Curculionidae), a polyphagous pest of citrus and other horticultural plants, was studied in laboratory assays designed to identify potential semiochemicals from host plants that might be exploited for weevil pest management. Using still-air bioassays, weevils were found to be most attracted to fresh whole lemon leaves compared with cut and/or dried lemon leaves. White clover, an understorey plant in kiwifruit orchards, was also found to be attractive to weevils in the dual-choice tests. Coupled gas chromatography-electrophysiological recording of weevil antennal responses to commercial extracts of lemon leaves indicated that weevils detected at least eight monoterpene components of the oil, i.e. linalool, terpinen-4-ol, nerol, neral, geraniol, geranial, neryl acetate and geranyl acetate. Significant antennal dose-responses were evident to lemon leaf oil, lemon constituent odours and two major green leaf volatiles detected from clover (Z)-3-hexenol and (Z)-3-hexenyl acetate. Still-air dual-choice tests on individual chemicals showed significant repellency from seven of the lemon leaf compounds at 500 mg/100 mL (all except geranyl acetate). Weevils were attracted to a synthetic blend consisting of the green leaf volatiles over a range of concentrations (1, 10 and 100 mg/100 mL), as well as to clover leaves. These plant kairomone components may be potentially useful as repellents or attractants for FRW control and management programme.

An electronically controlled aerosol system for mating disruption was evaluated against Epiphyas postvittana Walker in apple orchards in New Zealand. The area in which male moths were affected by the aerosol system was examined using catches in traps radiating from a central single-point source of either one aerosol can dispenser or 100 polyethylene tubing dispensers, compared with catches in orchard plots without pheromone dispensers. Both pheromone dispensing systems decreased moth catch to similar levels at 5–10 m from the central release point, but there was 5.5-fold more pheromone released from aerosol cans than from polyethylene dispensers over a 24 h period. Trap catches were reduced by about 90% in plots treated with either five aerosol cans per hectare or uniform deployment of polyethylene dispensers. Recordings of electroantennograms in open grassed plots and orchards indicated that the treated cotton pad of an aerosol dispenser and a point source of 100 polyethylene tubing dispensers produced similar electroantennogram recordings. Electroantennogram recordings provided evidence that pheromone plume detection from a single-point source was maintained over a range of 5–40 m downwind in the orchard. On present evidence, aerosol pheromone dispensers could not be recommended for further testing towards control of E. postvittana under New Zealand conditions owing to their higher cost of purchase and operation. Copyright © 2006 Society of Chemical Industry

Earwigs are significant generalist predators of a range of orchard pests, but quantitative assessment of earwig density and beneficial impact is difficult. A sampling system was designed and tested, based on field placement of polycarbonate tubes in apple trees as scotophase arboreal refugia. Tubes containing artificial diet and provided with a black plastic sleeve had the highest earwig counts. Tubes with diet or the black sleeve alone were less preferred. Presence of distinctive frass was also evident in polycarbonate tubes containing artificial diet, and earwig frass was recorded at a higher frequency than earwig presence, indicating foraging and detection of the tubes at a higher rate than their use as shelters. At the tree level, there was a weak correlation between frass abundance and predation rates on leafroller egg batches placed as baits in the canopy, but not with earwig density measured by corrugated cardboard rolls or diet tubes. Diet tubes have the potential to offer new insights into earwig foraging behaviour in orchards.

Live female painted apple moths are being used to monitor the distribution of this invasive species in Auckland as part of a major eradication effort, and the goal of this project was to develop a method to minimize the risk of unwanted live insect propagation from the trapping programme as a result of vandalism or 'eco-terrorism'. Female pupae were irradiated with a range of doses and their egg viability assessed, and also tested to determine the impact of irradiation on male moth catch in the field. Female painted apple moth pupae, irradiated at a range of doses from 100 to 500 Gy, were placed in cages in traps at 10 m spacings from non-irradiated females, near a central release site of irradiated males. Untreated control females alternated along orthogonal transects with irradiated females. The results indicated no significant effect of female irradiation on catch of males. There was no correlation between dose and catch, within the range of exposures tested. There was a very low hatch rate of eggs from females irradiated at all doses tested (100-500 Gy). These results suggest that irradiated females could be used in traps to reduce potential risks of deliberate spread of the unwanted organism by activists, without affecting the effectiveness of monitoring males.

Parasitism by the braconid wasp Dolichogenidia tasmanica of first instar larvae of the lightbrown apple moth Epiphyas postvittana, established on four different species of potted host plants, was assessed after 2 weeks of field exposure in an apple orchard. Parasitism varied significantly between larval host plants (apple 58%, broom 59%, clover 30%, poplar 19% ). Parasitism on potted apple seedlings of the co-evolutionary host, E. postvittana, was compared in a field trial with that of two native New Zealand leafroller species (to which D. tasmanica has had exposure for 5 decades only). Parasitism varied significantly with larval host (E. postvittana, 83%; Ctenopseustis herana, 58%;Planotortrix octo, 26% ). Larval collections were made from mature apple trees and identification of larvae was achieved by DNA analysis for the leafroller species using PCR-RFLP of ITS1 + ITS2, and for the parasitoid by specific PCR of partial 18S. Parasitism under natural field conditions on mature apple trees was not different between larval hosts (mean 32.5% ). In laboratory studies, more P. octo larvae departed in response to parasitoid probing behaviour than E. postvittana, which is likely to contribute to the difference in parasitism rates. This study conclusively shows that D. tasmanica parasitises native New Zealand leafrollers, despite their different evolutionary origins.

Phenology of the coffee plant and infestation by coffee berry borer #Hypothenemus hampei$ Ferrari were studied in relation to trapping of adult females in kairomone-baited traps in a coffee plantation in New Caledonia. In a 0.4 ha coffee field, a group of 27 trees located along a transect beginning at an early infestation point was selected. The number of green, red and dry coffee berries, along with the number of larvae, adult males and females per berry was determined monthly from October 1993 to July 1994. Twelve, red multifunnel traps, each baited with a solution of methanol:ethanol (1:1 ratio, a mean solution release rate of 1 g/day) were placed within the coffee field, along the transect, within the selected trees, grouped in four zones named 1-4. Two additional traps were located outside the plantation. The proportion of infested berries increased as berry maturity and harvest date approached, while the infestation rate decreased with distance from the epicentre. Over the 10 months of the study, beetle populations increased and spread from the original infestation point across the different zones, according to distance and availability of berries or appropriate physiological status. Traps near the epicentre caught the largest numbers of beetles. Linear relationship between trap catch and infestation level was demonstrated. Traps placed outside the field approached zero catch. Trap catch was highly influenced by rainfall events, and the highest captures coincided with rapidly declining berry numbers on trees. There are good prospects for management of this insect using traps. (Résumé d'auteur)

Larvae of Epiphyas postvittana and Planotortrix octo were released onto branches cut from apple trees, and allowed to colonize a range of types of artificial nests. Both species exhibited similar strong preferences for nests comprising leaf-leaf or leaf-fruitlet combinations, followed by nests comprising leaf-plastic leaf, leaf-plastic fruitlet or plastic leaf-fruitlet combinations. Nests involving fresh plant material alone (shoot, fruitlet or leaf alone) were also colonized to a lesser extent, but no larvae were found on nests consisting of plastic leaves or fruitlets alone or in combinations of the two. In another experiment, more E. postvittana larvae colonized nests with leaf and fruitlet combinations, compared to leaf and glass ball, or leaf and treated wax ball combinations, where the wax had been in contact with fresh apples or fruitlets. Choice tests, conducted using larval traps, showed that larvae were caught in traps baited with odors collected and released by wax which had been in contact with mature apples and leaves. Chloroform extracts from apple skin also caught larvae in choice tests. These results suggest that both physical and chemical cues are important to leafroller larval establishment.

Orientation disruption (indicated by reduced trap catch) of adult male Planotortrix octo (Lepidoptera : Tortricidae) was examined in eight small plot trials at four apple orchards over three years, using either (i) Z5-14 :OAC (inhibitor), (ii) a blend of 25 :75 Z5-14 :OAc and Z8-14 :OAc (inhibitor plus partial pheromone), or (iii) 50 :50 Z8-14 :OAc and 14 :OAc (pheromone) in polyethylene rope dispensers at 100 or 200 dispensers per 0.1 ha. Use of inhibitor plus partial pheromone gave significant reductions in trap catch in all eight trials. Inhibitor alone gave statistically significant reductions in catch in all three trials where it was tested, but was not as effective as the inhibitor plus partial pheromone in one of these trials. Three trials comparing efficacy between the pheromone and the inhibitor plus partial pheromone blend showed no difference between these blends. Analysis of covariance of trap catch after treatment, using the catch in the first generation in each trap as a covariate, was useful for detection of treatment effects. Traps containing the blend of Z5-14 :OAc and Z8-14 :OAC were not attractive, suggesting that false trails may not be important where this blend is used, since it is an incomplete pheromone and contains an inhibitor. Disruption of mating was examined in closed containers, with dispensers containing (i), or (ii). Mating frequency was 86.4% in the controls, compared to only 14.3% with the inhibitor present alone, or 1.7% with partial pheromone and inhibitor. The frequency of mating in scotophase within 1-8 h after termination of 24 h exposure to a very high dose of the non-attractive blend of 25% :75% Z5-/Z8-14 :OAC was identical for treated and untreated P. octo males.

Behavioral responses of newly-emerged codling moth (Cydia pomonella L.) larvae to α-farnesene were compared for a laboratory-reared strain (lab, 160 generations inbred) and a recently collected strain (wild, 3 generations). Video recordings of single larvae placed 20 mm from Bond papers releasing a range of seven α-farnesene concentrations were scored for head turning, head lifting, head direction, and movement across a Petri dish. The laboratory strain was significantly less successful at finding the treated papers than the wild strain. The lab strain was also significantly less active, shown by more random orientation, slower walking speed, less head turning and less head lifting. Both strains showed lower response to α-farnesene concentrations less than 10 -6 (w/v) α-farnesene. Orientation, walking speed, and head turning rate were significantly higher in the presence of α-farnesene concentrations >10 -7 w/v, for both strains. Head lifting did not show any effect from α-farnesene. Head turning was associated with both head lifting and walking speed and this association improved with the presence of α-farnesene. Increased attraction to odour source was correlated with improved direction finding at concentrations above 10 -7 w/v. Activity factors such as head turning and walking speed influenced time to locate odour source more than orientation factors. Odour-guided orientation to α-farnesene in codling moth larvae was composed of both locomotory, and to a lesser extent, orientation responses, which increased in a directed fashion to the stimulus.

This study identified markers in the ribosomal RNA gene complex (rDNA) and evaluated their utility in the differentiation of four endemic New Zealand species of leafroller moth, Planotortrix excessana (Walker), P. octo (Dugdale), Ctenopseustis herana (Felder and Rogenhofer) and C. obliquana (Walker). Pooled genomic DNA from laboratory-reared specimens of C. herana and C. obliquana could be distinguished with a single restriction enzyme (e.g. ClaI), while P. excessana and P. octo could be satisfactorily distinguished using double digestions with either ClaI/PvuII or ClaI/BglII. It is concluded mat these markers may be used to identify moths from wild populations.

The advantage of inherited sterility over complete sterility in lepidopteran sterile insect technique programs results from the improvement of mating fitness of male-only releases with wild females, and the resulting large multiplier effect from viable but sterile progeny from every mating. The deleterious effects induced by irradiation are inherited by the F1 generation, but it is very difficult to measure population introgression at that stage, and the alternative has been to await population suppression at the F2 generation. This work, conducted in support of the successful elimination of painted apple moth (Teia anartoides) in New Zealand, aimed to determine the feasibility of a cytological assessment on the F1 sperm bundles of this species, as a new forensic biosecurity tool providing information for decision support. The technique successfully distinguished the homogeneous nuclei clusters of eupyrene bundles of the normal fertile males from the heterogeneously stained nuclei clusters of the F1 progeny. However, the challenge for the technique involved obtaining good specimens for cytological diagnosis. The percentage of positive staining results was correlated strongly with survival, which was

Two related insecticide resistance management programmes are under way in New Zealand horticulture. The first aims to limit the spread and impact of azinphos-methyl resistant lightbrown apple moth (LBAM) in an applegrowing district. In the second, the introduction of pyrethroid (SP) resistance in organophosphate-resistant (OP) Typhlodromus pyri makes it possible to undertake biological control of the European red mite that is compatible with SP and OP control of orchard pests. In the LBAM programme the resistant zone, which includes alternative host-plant reservoirs, has been delineated by detailed resistance monitoring with topical application of males caught using female sex pheromone. In that zone, chlorpyrifos, to which the azinphos-methyl resistant LBAM has low cross-resistance, is used in the short term to control resistant moths, while alternative measures (e. g. other insecticides and mating disruption) are investigated. Recognition of the importance of immigration from alternative host plant reservoirs has led to specific tactics such as the application of pyrethroids to non-crop areas. This resulted in a significant decrease of the resistant population. So far, however, SPs have not been registered in apple orchards because they kill OP-resistant predatory mites which control the European red mite, and also because of the lack of residue tolerances for SPs in some overseas markets. Following the assessment of the potential value of pyrethroids in pipfruit, DSIR started field selection for pyrethroid resistance in predatory mites, which was later expanded to include laboratory selection. The successful development of pyrethroid-resistant predators which retain organophosphate resistance is permitting the introduction of biological control of European red mite compatible with the use of these two classes of insecticides for control of other pests. In future, the lepidopterous pests on New Zealand apples may be controlled by pyrethroids, scales and other minor pests by organophosphates, and European red mite by multi-resistant predatory mites.