Measuring the survival of White Peach Scale (Pseudaulacaspis pentagona) on kiwifruit (Actinidia chinensis var. deliciosa ‘Hayward’) in coolstorage in Italy

The survival of overwintering adult White Peach Scale (WPS) (Pseudaulacaspis pentagona) on kiwifruit (Actinidia chinensis var. deliciosa ‘Hayward’) in a commercial coolstore in Italy was measured using a biochemical live/dead test. Fruit infested with adult female (overwintering) WPS were collected from two Italian kiwifruit orchards at harvest in October 2016 and stored in a commercial coolstore at 0–1°C. The time required to kill 99% of the WPS on the fruit was 203 days (95% CI 199–208 days). Insect mortality did not rise above background rates until after 80 days in coolstorage. Mature WPS adults on fruit removed from the coolstore after 128 days were able to mature eggs normally, and subsequent crawler settlement was observed after 22 days out of coolstore at 20°C. Italian kiwifruit infested with WPS is imported into New Zealand during January and February each year, after a coolstore duration of 60–130 days. Most of the mature WPS will be alive and viable in terms of egg development and crawler production.