Bactrocera dorsalis, Zeugodacus cucurbitae, and Ceratitis capitata (Diptera: Tephritidae)]]>

摘要

We conducted no-choice cage and field infestation studies to determine if the fruit of kiwifruit (Actinidia chinensisvar. deliciosa, ‘Hayward’ [green-fleshed], andActinidia chinensisvar. chinensis, ‘Zesy002’ [gold-fleshed]) are hosts for three invasive tephritid fruit fly species that may enter New Zealand or other kiwifruit growing areas. For cage studies, punctured and unpunctured (intact) fruits of green and gold kiwifruit were exposed to gravid female flies ofBactrocera dorsalis(Hendel) (Oriental fruit fly),Zeugodacus cucurbitae(Coquillet) (melon fly), orCeratitis capitata(Wiedemann) (Mediterranean fruit fly), in screen cages outdoors for 24?h, and then held on sand in the laboratory for three weeks for pupal development and adult emergence. Unpunctured green kiwifruit produced an average of 1.3, 0.0 and 48.8 puparia per kg of fruit forB. dorsalis,Z. cucurbitaeandC. capitata, respectively. Unpunctured gold kiwifruit produced an average of 54.7, 6.1 and 0.0 puparia per kg of fruit forB. dorsalis,Z. cucurbitaeandC. capitata, respectively. For comparison, unpunctured papaya, a preferred host for all three species, produced 492–795 puparia per kg of fruit across all species. These results indicate that kiwifruit is a poor ovipositional host forB. dorsalis, Z. cucurbitaeandC. capitata. When kiwifruit were punctured to facilitate oviposition, the number of puparia per kg fruit increased significantly compared with those on unpunctured fruit forB. dorsalis,but not forZ. cucurbitaeorC. capitata, indicating that kiwifruit is a poor developmental host for these two species. For all fruit fly species, the average weight of individual puparia recovered from green and gold kiwifruit was roughly 50% of the weight of puparia recovered from papaya. Field infestation of kiwifruit suspended from papaya trees resulted in no infestation of green kiwifruit and very low infestation of gold kiwifruit byB. dorsalis, and no infestation in either cultivar byZ. cucurbitaeunder natural conditions. Overall, kiwifruit is a poor host forB. dorsalis,Z. cucurbitaeandC. capitata. This information will help inform decisions about quarantine restrictions and potential crop loss in the event of incursions of these fruit flies into New Zealand or other kiwifruit producing countries.