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The larval parasitoid, Thripoctenus javae (Hymenoptera: Eulopidae), was introduced into New Zealand in 2001 as a biological control agent for greenhouse thrips, Heliothrips haemorrhoidalis. We have re-evaluated the establishment of T. javae at the release sites from Kerikeri to Gisborne and surveyed kiwifruit orchards in the Bay of Plenty to determine how widespread the parasitoid has become. Release sites were surveyed in autumn 2017 for greenhouse thrips. Foliage samples were collected from numerous host plants, where greenhouse thrips were found, and the number of T. javae pupae on each leaf were recorded. In 2018, a second survey for T. javae was conducted in Bay of Plenty; samples of cryptomeria (Cryptomeria japonica) shelterbelt foliage were collected from 65 kiwifruit orchards. Foliage samples were washed and pupae of T. javae were counted. Thripoctenus javae were recorded at 80% of the original release sites from Kerikeri to Gisborne. The parasitoid was found at all sites in Whangarei and Bay of Plenty, 50% of sites in Kerikeri, 33% of revisited sites in Gisborne as well as the single site in Auckland. No host populations of greenhouse thrips were found at four release sites (Kerikeri = 2 and Gisborne = 2). In Bay of Plenty, T. javae were found at 32 kiwifruit orchards (49% of the total surveyed). All of these orchards are new locality records for T. javae. The furthest distance T. javae was found from a release site was 55.4 km. The introduction of T. javae into New Zealand has been successful with the parasitoid recorded at 80% of the original release sites after 17 years. Dispersal is evident in the Bay of Plenty where we have detected T. javae at 32 new locations on kiwifruit orchards. [ABSTRACT FROM AUTHOR]

The controlled atmosphere temperature treatment system (CATTS) was assessed as a disinfestation tool to control codling moth (CM; Cydia pomonella) larvae inside apples. Codling moth mortality and apple quality were assessed after exposure to one of 10 treatments, which were combinations of five variables, namely, O2 concentration (air 20.9%, 1, 2 or 3%); CO2 concentrations (air 0.04% or 15%); 12 or 24°C/h ramp rate up to 46°C; air speed 1.3 m/s; and either 2.5- or 3-h treatment time. CATTS treatments resulted in higher CM mortality than equivalent hot air treatments. The treatments involving 1 or 2% O2 combined with 15% CO2 and a ramp of 12°C/h or 24°C/h to 46°C, with a total treatment time of 3 h or 2.5 h and a 1.3 m/s air speed resulted in 100% mortality of CM. However, all CATTS and hot air treatments compromised apple quality. High CM mortality can be achieved using CATTS, but refinement of the protocol is needed to improve fruit quality outcomes. [ABSTRACT FROM AUTHOR]

New Zealand apples infested with apple leafcurling midge (ALCM) cocoons are a quarantine issue for growers exporting to many markets. The presence of ALCM on apples in these markets requires fumigation with methyl bromide, which decreases fruit quality. The effectiveness of various forms of heat treatments on ALCM were evaluated as alternatives. Apples infested with ALCM cocoons were subjected to one of the following heat treatments: Controlled Atmosphere Temperature Treatment System (CATTS; 1% O2, 15% CO2, 46°C, 3 h), hot air (46°C, 3 h), hot water high pressure washing (hot-HPW; 55°C, 100 psi, 15-20 s), or hot water drench (HWD; 55°C, 40 psi, 15-20 s). ALCM removal and mortality were assessed 7-days post-treatment. The hot-air and CATTS treatments provided the greatest control, with 82.2 and 92.2% mortality respectively. More cocoons were removed with hot-HPW (46.6%) compared with ambient-HPW (27.1%). Neither HWD nor hot-HPW increased mortality of cocooned ALCM over that in untreated controls. ALCM cocoons are particularly difficult pests to remove/kill; further research should focus on incorporating multiple control measures into the current systems approach. [ABSTRACT FROM AUTHOR]

Ethyl formate (EF) is used as a fumigant against insect pests on many commodities. Delivery of EF uses a carrier gas, usually carbon dioxide (CO2), to reduce its flammability. However, CO2 is expensive and can only be delivered relatively slowly. Nitrogen (N2) has been proposed as an alternative. The efficacy of EF delivered using CO2 or N2, was evaluated at 5 and 15°C, against two important postharvest pests of kiwifruit (greedy scale (Hemiberlesia rapax, Hemiptera: Diaspididae) and obscure mealybug (Pseudococcus viburni, Hemiptera: Pseudococcidae)). Mortalities of both insect species were higher in the presence of CO2 than N2. There was a strong interaction with treatment temperature: N2 at 5°C resulted in low mortality across both species. Greedy scale was more susceptible to EF than obscure mealybug across all treatments. Nitrogen as a carrier gas for EF substantially lowered the efficacy of EF as an insecticidal fumigant, relative to CO2 . This is hypothesised to be caused by differing respiration rates across temperatures and CO2 concentrations. Solutions for rapid CO2 delivery should be explored over further trials with N2 at low temperatures. [ABSTRACT FROM AUTHOR]