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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.

Export markets require highquality fruit free from insects and mites of quarantine significance and with minimal or no agrichemical residues This presents a challenge for New Zealands pipfruit sector when developing novel pest management systems to meet these market requirements Brushbed apple washers are an important component of a systems approach to remove insects and mites in packhouses before fruit are exported A new apple washer using multinozzle rotors significantly reduced the incidence of insects and mites on apples Weathered residues of kaolin and hydrated lime were similarly reduced by this apple washer Assessment of fruit quality after apple washing and cool storage did not identify any commercially significant quality issues on the three apple cultivars examined Apple washer design to optimise pest removal from all locations on the fruit is discussed

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 Zealand apple growers need to produce crops that satisfy conlicting export market requirements. Some markets want pest-free fruit, while others demand residue-free fruit. Pheromone mating disruption combined with the judicious use of insecticides enables crops to meet both demands. This study in 14 Hawke's Bay apple orchards showed that seasonal pheromone trap catch was reduced by 70%, from 40.1 codling moths/trap in the season before mating disruption was introduced to 11.7 moths/trap over the subsequent ive seasons. In the same period, insecticide use reduced from 5.9 applications/season in 2006- 07 to 2.3 in 2007-08 and 3.7 since 2008-09. The incidence of larvae in fruit where mating disruption operated averaged 0.01%, which was lower than in orchards using insecticides only. Damage increased from 2008-09 with greater reliance on codling moth granulosis virus over residual insecticides. Nevertheless, mating disruption with 3-4 insecticide sprays controlled codling moth to the high standard needed.

Codling moth ( Cydia pomonella) and leafrollers, principally lightbrown apple moth (Epiphyas postvittana), are key pests of apples. Pheromone mating disruption has until now required separate dispensers to be deployed for each pest group. With 600-1000 dispensers per ha for each species, application costs are a signiicant factor limiting the wider adoption of multi-species mating disruption in New Zealand apple orchards. The aim was to integrate the two disruption systems into a single dispenser, and evaluate its performance against that of separate dispensers, in paired block comparisons on four apple orchards. The three measures of effectiveness , pheromone trap catch, suppression of moth mating and fruit damage at harvest, all showed no statistical differences between the two treatments. The performance of the new combination pheromone dispenser was equivalent to that when the two dispensers were deployed separately.

The sale of pheromone traps lures and mating disruption products for horticultural insect pest species has grown steadily since the late 1980s with expanding sales to New Zealand growers from Plant Food Research (PFR) and its predecessors New biosecurity incursions led to pheromone identifications for delimitation and pest management of other species Mating disruption products were developed to target leafrollers currant clearwing codling moth and oriental fruit moth In 201011 the activity involved with production of > 30 pheromone products was sold as a business unit by PFR to a New Zealand company In addition the first legislative group standard for plant protection products was drawn up to enable future development of straightchained lepidopteran sex pheromones under New Zealands Environmental Protection Authority The availability of pheromone products to assist with decision support and pest management is now subject to market forces

Mealybug infestations in New Zealand apples declined when integrated fruit production was implemented in the late 1990s. In Hawke's Bay, however, mealybugs have recently become an increasing problem. The mean incidence of mealybugs at harvest increased from 1.7% in 2008 to 2.2% in 2010. In 2009 and 2010, almost 50% of blocks had a higher incidence than the previous year. Analysis of spray diaries suggested that spray programmes up to 2009-10 were inadequate to maintain long-term suppression of mealybugs. Key factors were the number of insecticide sprays, their time of application, and the choice of product, but not spray coverage. Consequently, in spring 2010, orchard managers were encouraged to follow a 'best practice' spray programme against mealybugs, which led to markedly improved mealybug control. At harvest in 2011, the mean incidence was 0.7% and just 14% of blocks had more mealybugs than the previous year while almost 60% had fewer.

The parasitoid Aphelinus mali controls woolly apple aphid (WAA; Eriosoma lanigerum) in New Zealand apple orchards. The effects of seven pesticides on A. mali exposed to residues on filter paper were assessed in a laboratory bioassay immediately post- application. Spinosad at label rate was moderately to highly toxic, but other compounds and lower rates of spinosad had no detrimental effects on A. mali. Another bioassay incorporating field application and exposure to aged residues on leaves determined the toxicity of carbaryl, diazinon, indoxacarb and lime sulphur. Carbaryl had the greatest residual toxicity to A. mali on harvested leaves, causing 85% mortality 21 days after application, declining to 40% by 28 days. In contrast, diazinon initially caused high mortality but residues were not toxic 15 days after application, while indoxyacarb and lime sulphur were not toxic. Minimising the use of pesticides toxic to A. mali should benefit the sustainable management of WAA in apple orchards.

Grapevine leafroll-associated Virus 3 debilitates grapevines, reducing yields and juice quality, and eventually makes vineyards uneconomic. Mealybugs (Pseudococcus spp.) are the key insect pests of grapes in New Zealand because they are the principal vectors of this virus. Until recently, all insecticides registered for their control depended on direct contact, but mealybugs live in hard-to-treat parts of vines. This research tested the efficacy of two neonicotinoid insecticides, imidacloprid and SCAL 5085, that have translaminar and systemic activity. Two field trials were conducted on commercial vineyards with the insecticides applied as soil drenches. In the first trial, imidacloprid applied at 0.525 g ai/vine reduced mealybug abundance by >99% compared with untreated vines, and autumn and spring applications were equally effective. Half this rate was less effective, although drenching in autumn was better than in spring. In the second trial, treatments were applied in winter, and SCAL 5085 at 0.263 g ai/vine provided equivalent control to imidacloprid at 0.525 g ai/vine.

Leafrollers are important pests of apples and infested fruit can result in rejection of export consignments. Leafroller mating disruption using a pheromone blend with activity against three species was examined in 12 Hawke's Bay orchards over two seasons (2009- 10 and 2010-11). Pheromone dispensers (600/ha) and a single insecticide were applied to trees in early November, and subsequent insecticide use was based on leafroller pheromone trapping and thresholds. The pheromone blend substantially suppressed mating of virgin female lightbrown apple moth in treated orchards and reduced male catch in pheromone traps by up to 98% compared with the season prior to implementation. Insecticide use for leafroller control decreased accordingly, from 2.1-2.7 insecticides per block in 2008/09 to 1.0-1.8 in 2010/11. Leafroller control using mating disruption was acceptable, fruit damage varied from 0.3% to 0.16% and no leafroller larvae were found on fruit in both field assessments and phytosanitary inspections of packed cartons.

Bronze beetle (Eucolaspsis sp Coleoptera Chrysomelidae) threatens the economic viability of New Zealands organic pipfruit industry Small plot cultivation trials were conducted during spring to target immature beetles in the soil under apple trees These treatments did not appear to be as effective in the second year as in the previous year although two cultivations significantly reduced beetle emergence at all orchards compared with the control In largescale cultivation trials two cultivations reduced damage to apples by 4661 Sampling immature development stages of the beetles in the soil indicated that cultivation should commence during mid October to target pupae in the top 70 mm of the soil The application of cultivation treatments for controlling bronze beetle on commercial orchards is discussed

The New Zealand horticultural sector has made substantial progress in pesticide risk reduction by implementing sustainability programmes. Apple and winegrape pesticide use was analysed to measure changes in human and aquatic eco-toxicity arising from these initiatives using the Hazardous Substances and New Organism 1996 Act (HSNO) classification system. In 1995 insecticide use on apples and winegrapes was 11.6 and 0.31 kg ai/ha respectively, while fungicide loadings were similar, about 30 kg ai/ha. Since then insecticide loading on apples has decreased by 80% with much lower potential human toxicity. Growers following Integrated Fruit Production guidelines reduced fungicide loadings by 45% but expansion of organic apple production increased the sector’s total fungicide use. The wine sector has reduced their total agrichemical loading of insecticides by 72% and fungicides by 62%, mostly through lower use of sulphur fungicides. Both sectors have reduced their use of agrichemicals that are potentially toxic to aquatic ecosystems.

Mealybugs (Hemiptera Pseudococcidae) are the most important insect pests in New Zealand vineyards because they vector grapevine leafroll virus which seriously debilitates vines and reduces wine quality A field trial was conducted on a commercial vineyard using the insecticides prothiofos (Tokuthion) and buprofezin (Applaudtrade;) Factors tested were the timing and number of applications water rate (250 500 or 1000 litres/ha) and inclusion of an alkylsilicone or organosilicone spreadertype adjuvant Prothiofos was applied in late September (late dormant) while buprofezin was sprayed at late dormant mid October and late November (preflowering) The best treatments for reducing mealybug numbers and proportion of infested leaves were prothiofos at late dormant and two later applications of buprofezin Two applications of buprofezin were more effective than one more than halving the number of mealybugs A water rate of 500 litres/ha was equally as effective as 1000 litres/ha None of the three adjuvants improved the efficacy of prothiofos or buprofezin

Bronze beetle (Eucolaspsis sp Coleoptera Chrysomelidae) threatens the viability of New Zealands organic pipfruit industry Small plot cultivation trials were conducted during spring to target immature beetles in the soil in a 25 m strip under apple trees A single cultivation treatment in October prevented 56 to 81 of the beetle population from emerging When plots were tilled every second week from October to December 79 to 95 failed to emerge The pattern and timing of bronze beetle emergence during 2006 was consistent between the four trial orchards and with the 2005 season A survey of 20 orchards during November 2006 was unable to link beetle damage levels with management practices and the physical environment New strategies to manage bronze beetle larvae are discussed

Leafroller larvae especially Epiphyas postvittana damage grape bunches and more importantly promote spread of the disease botrytis (Botrytis cinerea) Three methods of monitoring leafrollers were compared on 10 Hawkes Bay vineyard blocks The methods were timed searches of leaves for larvae inspection of bunches for larvae and pheromone trapping of adult males Seasonal changes in leafroller abundance were similar on all vineyards Usually few larvae were found until February but infestations increased greatly between then and March In other respects leafroller infestations were variable between and sometimes within blocks None of the monitoring methods was completely successful The most useful method was bunch inspection primarily because of the close correlation between bunch infestations in January and at harvest However this method is relatively laborious and did not give enough warning to enable use of some insecticides Leafroller infestations on leaves in all months and pheromone trap data were poor predictors of harvest bunch damage

Grapevine leafroll disease in New Zealand is predominantly caused by the ampelovirus GLRaV3 which is vectored between vines by up to three species of mealybugs (Pseudococcus spp) However global understanding of the transmission and spread of GLRaV3 remains limited and does not definitively show how to successfully manage the disease in New Zealand The disease is a manifestation of a complex relationship between the virus vine and vectors each component of which is interdependent on the other two The review suggests that a full understanding of the disease will require research and operational input from plant virologists entomologists vine physiologists pest controllers vineyard managers grapevine breeders/improvers and winemakers Such a wide range of expertise should ensure that the factors behind the spread of the disease over time (its epidemiology) are accurately determined and that effective management solutions are delivered over the course of decades

A laboratory bioassay was used to evaluate the effect of residues from 10 orchard pesticides on mortality of Dolichogenidea tasmanica a parasitoid of leafrollers Adult parasitoids were caged in Petri dishes that had been sprayed with the field rate of the pesticides Mortality was assessed over 7 days and classified using the laboratory criteria defined by the International Organization for Biological and Integrated Control of Noxious Animals and Plants Residues of buprofezin emamectin benzoate lufenuron tebufenozide and thiacloprid were harmless (lt;30 mortality) to D tasmanica adults in the 7 days after treatment Indoxacarb and lime sulphur residues were moderately harmful (8099 mortality) while carbaryl diazinon and spinosad residues were harmful (>99 mortality) The implications for leafroller control in pipfruit production programmes are discussed

Leafrollers (Tortricidae) were collected from apple foliage and understorey vegetation in six commercial organic apple orchards in Hawke’s Bay over one season. Assessments were made of plant species present in the understorey at the time of collection. All leafroller larvae were reared to adults on artificial diet to identify leafroller species and parasitoids. Nearly half (47%) of all leafrollers collected in these orchards were located in the understorey, highlighting the importance of understorey and its management for the control of leafroller. Dock, clover and dandeliontype plants contributed 25% to the overall understorey, yet hosted 75% of the leafrollers collected from the understorey. Dolichogenidea sp. was the most abundant parasitoid (79%) attacking leafrollers found amongst the apple foliage, whereas Glyptapanteles demeter was dominant in the understorey (61%). Generally the number of leafrollers in an orchard was proportional to the abundance of broadleaf weeds and inversely proportional to parasitism.

Pheromone traps were operated in five regions to determine the impact of trap colour on catch of target and nontarget insects Red or green coloured pheromone sticky traps caught fewer native and introduced bees compared to the standard white traps and yellow or blue traps Honey bees (Apis mellifera) were caught mainly in white followed by blue traps while bumble bees (Bombus spp) were most attracted to blue traps with most of the remainder caught in white traps Native bee (Lasioglossum and Hylaeus spp) catches were greatest in white traps followed by yellow traps with a few in green traps There was no significant difference in catch of the target species Cydia pomonella or Epiphyas postvittana with trap colour Replacement of the white traps with green or red traps is recommended to reduce nontarget impacts on bees

In orchards using New Zealand Integrated Fruit Production for pipfruit (NZIFP-P), the decision to treat for leafroller (Lepidoptera: Tortricidae) results from sampling of 200 fruit clusters or 200 shoots. This required a large time commitment by the grower, was subject to misidentification and was a poor predictor of damage at harvest. In 1996-97, cumulative trap catch of Epiphyas postvittana (LBAM) within NZIFP-P research plots was found to be highly correlated with damage at harvest and a cumulative catch of 30 moths after 15 December was established as a tentative threshold. Insecticides were to be applied at least 21 days apart during periods of high trap catches. In 1997-98, this threshold was successfully used by 300 growers and using their trap data, the effect of increasing the threshold to 50 was examined. The 50 moth threshold is not appropriate in Otago, but in northern regions shows some potential and requires further evaluation.

Apple orchardists in Twyford, Hawke’s Bay, have reported increased fruit damage by leafrollers for several years. Of the three pest species present in this area, Planotortrix octo (greenheaded leafroller), is the main species found on fruit. First instar P. octo larvae were screened for resistance by a direct spray test using a Potter tower. Dosage-mortality responses for the offspring of wild-wild pairs from three orchards showed a 7-32 fold resistance to azinphos-methyl compared with larvae from a susceptible laboratory colony. P. octo larvae from one of the above and 16 further orchards were sprayed with a single diagnostic dosage (LD 99 for the susceptible strain). Resistance was found at 17 of 19 sites covering approximately 1000 ha. A resistance management strategy, using pheromone mating disruption, is being implemented.

Woolly apple aphid Eriosoma lanigerum (Hausmann) populations were monitored at the Appleby Research Orchard near Nelson (1994/ 1996) in two apple cultivars as part of an experimental Integrated Fruit Production programme which included the insect growth regulator insecticide tebufenozide. The aphid population increased dramatically during the first season in one cultivar (‘Sturmer Pippin’) from mid February and reached 90% shoot infestation by late summer. Parasitism of the aphid by the specific endoparasitoid, Aphelinus mali (Haldeman), was first recorded in late March 1995 and peaked at 13% by the end of April 1995 when monitoring ceased. In the second season the parasitoid was present from early summer and >80% parasitism was recorded by late April 1996. Aphid control was achieved without the need for specific aphicide sprays. The results indicate the potential for biological control of woolly apple aphid by A. mali within a selective insecticide

Agrichemical users face increasing pressures to adhere to and document safe and responsible use practices Many requirements are set by the Resource Management (RMA) and Hazardous Substances and New Organisms (HSNO) legislation Additional use and user requirements are dictated by market expectations for residues and adherence to different GAP programmes Widespread adoption of industry relevant user training programmes is arguably the most effective way to achieve safe and effective agrichemical use in New Zealand RMA requirements under all Regional Plans in the country require some level of agrichemical user training with HSNO legislation requiring separate approved handler (AH) certification for at least one person on most properties With over 50000 farms and horticultural properties in NZ the estimated agrichemical user trainee population is well over 100000 people GROWSAFE and AH certificate numbers from 200409 after the 2004 enactment of the HSNO legislation for agrichemicals averaged 9900 per annum These certificates are required to be renewed every 5 years but average trainee numbers from 200812 dropped to only 4950 per annum Training requirements and outcome expectations are reviewed in light of these declining trainee numbers and a new industryfocussed training initiative is described

Spray Plan Manager (SPM) is a decision support tool that helps users manage and document agrichemical use plans for compliance and for environmental and user risk reduction Refined and relaunched in 2013 at wwwsprayplanconz SPM has a base user group of 1700 registered plans across 76 crop types SPM takes agrichemical users through a stepwise property spray plan development SPM uses online GIS mapping to assist in agrichemical risk management around identified sensitive areas SPM uses agrichemical HSNO hazard classifications to describe personal protective equipment requirements for agrichemical mixing and application operations For ongoing management of boundary and sensitive areas spray drift risks can be estimated using forecast wind speed wind direction humidity and temperature SPM ranks drift conditions on a scale from 1 (suitable) to 4 (unsuitable) and displays the usersupplied forecast directional risks on the property map This has introduced a near realtime management component into annual spray plan operations Annually produced property spray plans are an agrichemical use requirement under most regional plans The new SPM was designed to assist users in this compliance task while also improving user education and outcomes around the safe effective and responsible use of agrichemicals

A dispenser incorporating a pheromone blend to disrupt three species of New Zealand leafrollers was developed for their control in Otago summerfruit orchards. This control system was evaluated for suppression of leafroller activity in Hawke’s Bay apple and summerfruit orchards over 2 years. In 2007-8, dispensers were applied at 600-1000/ha in two large organic apple orchards and activity of all three species in pheromone traps was recorded. Dispensers achieved only 73.8% and 61% shut-down of lightbrown apple moth pheromone traps in Orchards A and B respectively. Dispensers were modified to increase disruption of this species and were evaluated in similar trials on the same orchards in 2008-9, and achieved 98.4% and 90.9% trap shut-down respectively. The same dispenser was also evaluated on four summerfruit orchards, where it was applied to 1 ha plots in January 2009 at 1000 dispensers/ha. Pheromone trap catches of lightbrown apple moth were reduced by 83.3–100% over the following 3 months. Further assessment of this multiple species mating disruption system is required to determine its value in managing the fruit damage and larval infestation risks to meet export market tolerances.