Three species of armored scale (Hemiptera: Diaspididae) are found on kiwifruit (Actinidia spp.) in New Zealand orchards: latania scale, Hemiberlesia lataniae (Signoret); greedy scale, Hemiberlesia rapax (Comstock); and oleander scale, Aspidiotus nerii (Bouché). Each of them is a quarantine pest in some of the markets to which New Zealand kiwifruit are exported. Adult females of the three species can be distinguished morphologically; however, the task is laborious when large numbers must be identified. Furthermore, it is not possible to distinguish among the immature stages. A DNA-based diagnostic using a multiplex polymerase chain reaction (PCR) method based on differences in the cytochrome oxidase I and II genes was developed to distinguish the three species. The test relies on the rapid isolation of amplifiable DNA by using a protease (prepGEM), followed by multiplex PCR using primers that distinguish the species at three or more nucleotide positions within cytochrome oxidase I and II, resulting in PCR products of characteristic size for each species. The test was validated in a double-blind experiment and then used to determine the relative distribution and abundance of the three species on leaves and fruit of 'Hayward' and 'Hortl6A' kiwifruit across the dominant growing regions throughout New Zealand during the 2007 season. In total, 3,418 scale insects were identified to species level: 1,904 (56%) were latania scale; 1,473 (43%) were greedy scale; and 41 (1%) were oleander scale. Since the last survey in 1988, latania scale has displaced greedy scale as the dominant species of armored scale on Hayward kiwifruit in the North Island and was found for the first time in the South Island. Only a single latania scale was found on Hortl6A fruit, consistent with previous reports of reduced rates of settlement on the fruit of this cultivar by latania scale compared with greedy scale.

Spirotetramat (Movento† ) is a phloem-and xylem-mobile insecticide developed and registered for use pre-flowering to control armoured scale insects on kiwifruit vines in New Zealand. In a field study in 2010Á11, the effectiveness of a postharvest application was investigated. A single spray of spirotetramat plus adjuvant(s) reduced the percentage of scale-infested fruit from 49% on control vines to less than 7.5% on spirotetramat-sprayed vines 12 months later. No residues were detected in the fruit. Applying spirotetramat with a penetrating adjuvant (Engulf † ) provided the best result, with only 1.5% of the fruit infested. Despite the high pest pressure, counts of scale insect crawlers on sticky bands remained very low for 18 months after treatment. Uptake of spirotetramat into the mature kiwifruit leaves occurred in less than 24 h and was not affected by leaf age. Translocation out of the leaf was slow and decreased with leaf age, indicating that a postharvest spray should not be applied to canopies exhibiting advanced senescence. These results show that a single postharvest application of spirotetramat plus adjuvant(s) can provide excellent season-long control of armoured scale insects on kiwifruit while minimizing the risk to crop pollinators and the potential for residues in fruit.

Citrus red mite (CRM) populations can reach high levels in citrus orchards after the application of broadspectrum pesticides to control other pests It is important to know which are the key biocontrol agents of CRM in New Zealand in order to minimise use of pesticides toxic to these natural enemies CRM and natural enemies were monitored in seven orchards from January 2004 to March 2005 Ladybirds Stethorus sp and Halmus chalybeus and predatory mites Agistemus longisetus Amblyseius largoensis and Phytoseiulus persimilus were observed consuming CRM Stethorus sp and A longisetus were the most abundant natural enemies found with CRM The presence of 05 live Stethorus sp per leaf and 051 A longisetus per leaf was associated with the decline of CRM populations (15 eggs and 15 juvenile/adults per leaf) to trace levels in 45 weeks The use of neonicotinoid products can disrupt the predatory activity of Stethorus sp against CRM

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