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The potential for immigrant adult codling moths, Cydia pomonella (L.), to reduce the efficacy of the granulovirus (CpGV) against a univoltine population was investigated using published life tables for codling moth on apple trees in Nelson, New Zealand. Simulated life tables over eight generations incorporated mortality >90% from CpGV sprays and combined this with immigration rates ranging from 0 to 1 adult per tree. Without immigration, there were 5 damaged fruits per million by the eighth generation from an initial population of 1.22 adults per tree but only 9 per 100 million had fresh damage or larvae that could trigger phytosanitary rejection. Higher-yielding modern orchards reduced this fresh damage to 5 per 100 million harvested fruit. New Zealand exports apples to markets with zero tolerance of codling moth (Codling Moth Sensitive Markets [CMSM] programme), and immigration of 1 female per 100 trees was projected to pose a risk of failure to meet quarantine requirements with one freshly damaged fruit per 112,000, or per 202,000 in a modern high-density orchard. This confirms the wisdom of using an integrated suite of control methods in CMSM, of which CpGV is only one. Similarly, immigration of one female per 1000 trees or 3 ha had much lower risk but could also threaten exporting if reliance was placed solely on CpGV, with one fresh damage or larva per 2 million harvested fruit. A commitment to the removal of neglected host trees of codling moth in the environs of orchards is recommended. [ABSTRACT FROM AUTHOR]

The potential for the newly established ichneumonid Mastrus ridens (Horstmann) to provide biological control of codling moth, Cydia pomonella (L.), was simulated by incorporating different rates of parasitism into previously published life tables for a univoltine codling moth population on unsprayed apple trees in Nelson, New Zealand. Simulations over eight years were conducted using high and low initial codling moth densities, as occur respectively on neglected apple trees and commercially managed orchards. Life table simulations without M. ridens served as control treatments for comparison with simulations that included various rates of parasitism by each of the estimated three annual generations of the parasitoid. Based on the percentage parasitism recorded in New Zealand and the international literature, M. ridens is projected by the models to provide a valuable reduction of codling moth populations on neglected host trees in Nelson and thereby reduce the numbers of immigrant adult moths invading commercial apple orchards. In contrast, the codling moth is maintained at such extremely low densities within commercial apple orchards growing fruit for export that M. ridens is projected to make only a small contribution to parasitism within the orchard. These simulation results confirm the validity of the rationale for the introduction of M. ridens to New Zealand, which aimed to reduce the numbers of immigrant codling moths arriving in orchards from highly infested and neglected host trees in the wider environment. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

[Display omitted] • Mastrus ridens is a specialist parasitoid of codling moth from its area of origin. • Laboratory populations differing in time in captivity differed in some fitness traits. • The most recent laboratory population from Chile had better fitness parameters. • F1 Females with a Chile mother had better fitness, with no effect of father origin. • There were no benefits of crossing populations, but there were maternal effects. Populations of natural enemies in classical biological control programs often undergo recurring bottlenecks during importation and rearing, which can result in lower genetic variability and fitness. Enriching colonies with wild individuals, multiple importations or combining populations from different origins may help reduce this problem. Mastrus ridens (Hymenoptera: Ichneumonidae), a gregarious idiobiont ectoparasitoid of codling moth (Cydia pomonella) larvae was introduced to New Zealand from laboratory colonies dating to the 1990s. To improve populations for release, individuals from a most recent collection were imported from Chile (CL). Tests were conducted to measure genetic diversity of the parental populations (F0) and fitness traits of pure and mixed combinations of NZ and CL populations for F0 and the F1 generations. Results showed several effects depending on the population origin. CL females and males in the F0 generation lived longer than NZ females and males. Offspring from a CL mother lived longer than those from a NZ mother, and F0 and F1 females from a CL mother parasitized more larvae than females from a NZ mother. Genetic diversity estimates of F0 CL and NZ populations were 24% and 17% heterozygosity, respectively, and the NZ population had a larger proportion of diploid males than the CL population. Thus, no improvement in reproductive output resulted by mixing NZ and CL populations, as hypothesized, but a maternal effect was found in this species. This study shows the importance of understanding and tracking imported populations' genetic diversity and fitness traits in classical biological control programs. [ABSTRACT FROM AUTHOR]

Abstract: An organic orchard was planted at the Clyde Research Centre, Central Otago, from 1991 to 1993 on land not previously used for fruit-growing. The orchard comprised nine discrete 0.22ha well-sheltered apple (Malus domestica Borkh.) and pear (Pyrus communis L.) cultivar blocks with wide headlands, in a total land area of 3ha. Colonisation of the orchard by codling moth (Cydia pomonella L.) was monitored using pheromone traps and by recording larval damage to the fruit, initially, from examination of the entire crop of all the trees, then later a sample of the trees whose locations were noted. This facilitated a 3-dimensional record of orchard colonisation. Detailed examination of damage enabled estimation of the numbers of damaging larvae, their mortality in the fruit, and the numbers of larvae which survived to seek cocooning sites. A low density of 3–6 female codling moths was estimated to be present in the 2ha of planted orchard area in the first cropping season (1993–94). A major increase in trap catches and larval damage in 1995–96 prompted the application of mating disruption in the following years. Although successful in reducing the population for the first two seasons, codling moth then increased again and granulosis virus (CMGV) was added to the management programme. Three full rate sprays of the CMGV applied to the three central rows of each cultivar block in 1998–99 halved the percentage of fruit with surviving larvae to 0.7% in the treated trees. This fell to 0.2% in 1999–2000 following 13 applications of CMGV at 1/5th rate to the whole orchard. In 2000–01, when mating disruption was again used alone against a low density population, only one surviving larva was found in a sample of 11,841 fruits (0.05%). The complementary management options provided by mating disruption and CMGV are discussed, as well as the importance of minimising the sources of immigrant codling moths near organic orchards. [Copyright &y& Elsevier]

The article discusses a study on the codling moth, Cydia pormonella and its behavioral response to kairomone, codling moth sex pheromone and sex pheromone with the pear-derives kairomone in New Zealand apple orchards. Codling moth, Cydia pormonella is the main pest on some fruits worldwide especially in New Zealand. In order to manage codling moth, the codling moth sex pheromone has been used in monitoring and detection for optimization of insecticide spray and mating disruptions. In this study, kairomone baited traps can be used in monitoring the flight activity of female C. Pormonella in apple orchards but the sex pheromone should be used continually in monitoring male activity.

Simple Summary: Codling moth is a major pest of apples, and was accidentally introduced into New Zealand over 150 years ago. Many countries that New Zealand exports apples to do not have codling moth present and they want to keep it out. Therefore, apple growers must heavily control codling moth populations on their orchards. Currently, the main control tactics are insecticide applications and mating disruption, which uses the moth's own sex pheromone to make the males unable to find females to mate. We aimed to supplement these tactics with the sterile insect technique (SIT) to further suppress the codling moth on orchards. SIT involves mass rearing and sterilizing codling moth and then releasing them onto orchards where they mate with wild insects resulting in no offspring. We released sterile insects onto seven orchards using unmanned aerial vehicles and ground releases. Six years of the program saw significant drops (90–99%) in wild moth populations. The SIT is an excellent tactic for reducing moth populations in export apple orchards. 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 90–99% lower than in 2013–2014, the year before releases began. Catches at three other IFP orchards (129 ha) decreased by 67–97% from the year before releases began (2015–2016), from lower initial levels. At a certified organic orchard with a higher initial population under only organic larvicides and mating disruption, by 2019–2020, there was an 81% reduction in wild moths capture from 2016–2017, the year before releases began. [ABSTRACT FROM AUTHOR]

Codling moth, Cydia pomonella (Lepidoptera: Tortricidae), is a phytosanitary pest of New Zealand's export apples. The sterile insect technique supplements other controls in an eradication attempt at an isolated group of orchards in Hawke'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. [ABSTRACT FROM AUTHOR]

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—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. [ABSTRACT FROM AUTHOR]

The effect of direct immersion in hot water at 43-49 deg. C on the mortality of 1-, 3-, and 5-d-old eggs and 1st, 3rd, and 5th instars ofthe tortricid Cydia pomonella (L.) was evaluated. The 1st instar wasmore tolerant than all other life stages of C. pomonella at all of the temperatures tested. Third and 5th instars were typically the nextmost tolerant life stages, and hence larvae were more tolerant than eggs. There were no significant differences between the responses of eggs of different ages. C. pomonella is more tolerant than other New Zealand tortricid pests of quarantine concern when exposed to hot water in the absence of the host fruits. [ABSTRACT FROM AUTHOR]