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New Zealand apple exports must meet strict phytosanitary measures to eliminate codling moth (Cydia pomonella Linnaeus) (Lepidoptera: Tortricidae) larval infestation. This study was part of a program attempting the localized eradication of codling moth within an isolated cluster of seven orchards (391 ha). A conventional management program of insecticide sprays and pheromone mating disruption was supplemented with weekly releases of sterile moths for 1–6 yr. Our objective was to compare the recapture rate of sterile moths following their release by four methods, and the efficiency of each system. The methods were the following: a fixed-wing unmanned plane flying ~40–45 m high at 70 km/h, an unmanned hexacopter travelling 20 m high at 25 km/h, and manually from the ground via bicycles or motor vehicles. The different release methods were used in different years or weeks. Sterile male moths were recaptured in grids of pheromone traps positioned throughout each orchard. The highest recapture rate followed delivery by hexacopter, then bicycle, vehicle, and plane. There was a 17-fold difference in catches between releases by hexacopter and plane, and sixfold between vehicle and plane in the same season. Bicycle delivery had a 3.5-fold higher recapture rate than the plane in different years. The wind-borne horizontal drift of moths was investigated as a possible explanation for the disparity of recaptures between the two aircraft delivery systems. The methods in ascending order of time per hectare for delivery were the following: plane and vehicle, hexacopter, then bicycle. The advantages and disadvantages of each moth delivery method are discussed.

Sticky traps for monitoring insects use polybutene adhesive (PBA) to entangle insects. This glue is effective but messy to use and an alternative, hot-melt pressure-sensitive adhesive (HMPSA) is available. The effectiveness of these two adhesives was compared for catching pest and beneficial insects, primarily in apples. Various types of trap with either PBA or HMSPA were placed in orchards and vineyards in Hawke’s Bay and Nelson. Eight pests from six families, six parasitoids, five predators and one pollinator were commonly recorded. Traps with HMPSA generally caught similar numbers or more of both insect pests and beneficial insects than traps with PBA. Traps with HMPSA performed better for larger insects (>1.5 mm), whereas those with PBA tended to be more effective for smaller insects. Both types of adhesive were effective for up to 4 weeks. HMPSA was effective for monitoring a range of insect pests and beneficial insects. Compared with PBA, HMPSA was more consistent and much cleaner and easier to use. It is recommended that HMPSA replaces PBA in traps for monitoring moth pests in the pipfruit industry.

Since of the first sex pheromone and the adoption of pheromone in pest management, the global pheromone market size has grown to reach USD 2.4 billion per year in 2019. This has enabled the development of environmentally friendly approaches that significantly reduce the application of pesticides. Recently, there have been reports of the failure of various commercial codlemone: (E,E)-8,10-dodecadien-1-ol formulations used for monitoring the apple pest codling moth, Cydia pomonella (L.). This work was initiated to investigate factors behind the lack of efficacy of codlemone lure in the Northern Hemisphere (Germany) and Southern Hemisphere (New Zealand). We hypothesised that the observed failure could be due to two main factors: (a) a shift in the response of male codling moth to codlemone and (b) degradation of codlemone under field conditions that renders the lure less attractive. Field trial tests of various doses and blends containing minor pheromone compounds suggested no change in response of male codling moth. The addition of an antioxidant and a UV stabiliser to codlemone resulted in a significant increase in the number of males caught in Germany, but not in New Zealand. Mean maximum temperatures during the growing season since 2004 indicate a 3 °C increase to 35 °C in Germany, but just a 1.5 °C rise to 30 °C in New Zealand. Chemical analysis of the lures used in the field trials in Germany and New Zealand indicated more degradation products and reduced half-life of the lures in Germany compared with those in New Zealand. Heating codlemone lures to 32 °C significantly reduced the number of males caught in traps and increased the isomeric and chemical impurities of codlemone compared with unheated lures. Our data provide the first evidence that climate change affects pheromone molecule stability, thus reducing its biological efficacy. Our finding suggests that climate change could be a general problem for chemical communication and, therefore, could affect the integrity of natural ecosystems.

Apple leafcurling midge (ALCM) is an important quarantine pest of New Zealand apples. Current methods for ALCM control have difficulty meeting the strict phytosanitary standards of some export markets. ‘Lure and kill’ is a new strategy against this pest, in which males are attracted to an insecticide-treated substrate where they collect a lethal dose. Trials were conducted using a gel matrix “Specialized Pheromone & Lure Application Technology” (SPLATâ„¢) to dispense and release the ALCM sex pheromone and the insecticide permethrin. Lures using SPLATâ„¢ were placed within plastic cylinder traps that collected the dead midges so they could be counted to determine treatment efficacy. The size, shape and age of SPLATâ„¢ spots influenced midge catches. Higher catches occurred with spots having a larger quantity of pheromone, greater surface area of SPLATâ„¢, or with fresh material. The implications for the development of a lure and kill strategy for ALCM are discussed.

Apple leafcurling midge is an important quarantine pest for New Zealand apple exports. Season-long pheromone trapping was conducted in Hawke’s Bay and Nelson from 2004—2017, and from 2012—2017 in Central Otago. Four generations occurred annually in Hawke’s Bay and Nelson and 3—4 in Central Otago. In Hawke’s Bay and Nelson, the timing of each peak varied by about 3—4 weeks between years, while the difference was ~2—3 weeks in Central Otago during fewer years of monitoring. Hawke’s Bay was up to a month earlier than Central Otago for the same peak within individual years. The major factor behind this variability was the accumulated number of growing degree-days. Insecticide sprays target midge larvae, but are timed against the second and third peaks of adult emergence. Variations in the timing of these peaks annually and across the main pipfruit growing regions, mean that specific insecticide timing recommendations are necessary each year for each region.

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

Pest management in New Zealand's pipfruit Integrated Fruit Production (IFP) programme relies on selective pesticides, biological control and pheromone mating disruption. The current situation is potentially precarious and one concern, the impact of less selective pesticides, was tested. Apple trees received synthetic pyrethroid (deltamethrin) sprays during the first half of two growing seasons. Beneficial and pest species were monitored monthly from November to April. Treated trees had fewer predatory bugs (91- 100% reduction), lacewings (64-100%), earwigs (80-100%), predatory mites (67-100%), spiders (20-64%) and Hymenoptera (16-49%) than untreated trees. Ladybird numbers varied depending on the assessment method. Outbreaks of phytophagous mites and woolly apple aphid occurred on treated trees, but there were fewer apple leafcurling midge, San Jose scale and Froggatt's apple leafhopper on untreated trees. Factors that make pest management under IFP vulnerable in the future, include a loss of biological control and the consequences of new pests establishing.

New pest management practices in New Zealand's apple sector have provided ecological and economic outcomes that are recognised by growers and exporters. Integrated Fruit Production (IFP) pest control systems that combine biological control, selective insecticides and mating disruption have been developed to achieve these outcomes. Although pest management in apple orchards is now more sustainable, it is also highly vulnerable to pesticide-induced disruption. The toxicity of four pesticides (spinetoram, thiacloprid, spinosad and spirotetramat) on the natural enemy of woolly apple aphid, Aphelinus mali, was examined. While applications of spinetoram were the primary cause of aphid outbreaks in 2007-08, other insecticides can contribute to the instability of this biocontrol system. The consequences of applying these disruptive pesticides to aphid control are discussed, together with strategies to mitigate the vulnerability of the IFP programme to pest outbreaks.