Field study demonstrates that exotic parasitoids (Hymenoptera: Encyrtidae) of mealybugs (Hemiptera: Pseudococcidae) are absent from a native forest habitat in New Zealand

• Published in: BioControl (Dordrecht, Netherlands) Vol. 60; no. 1; pp. 13 - 25
• Main Authors: Charles, John G, Forgie, Shaun A, Chhagan, Asha, Edwards, Robert D
• Format: Journal Article
• Language: English
• Published: Dordrecht Springer-Verlag 01.02.2015; Springer Netherlands; Springer Nature B.V
• Subjects: Agriculture; Animal Biochemistry; Animal Ecology; Aphelinidae; Behavioral Sciences; Biological control; biological control agents; Biomedical and Life Sciences; Citrus; Coccoidea; Encyrtidae; Entomology; Experiments; Forests; Habitats; Hemiptera; host range; Hymenoptera; Indigenous species; Introduced species; Laboratories; Life Sciences; Orchards; Parasitoids; Plant Pathology; Platygasteridae; Platygastridae; Pseudococcidae; Pseudococcus; Pseudococcus longispinus; rearing; New Zealand; Exotic parasitoids; Native parasitoids; Long-tailed mealybug; Risk assessment
• ISSN: 1386-6141; 1573-8248
• DOI: 10.1007/s10526-014-9619-2

Laboratory-based, physiological host-range tests of classical biocontrol agents may be complemented by examining the ecological (realised) host-range of similar, previously established species. Sentinel long-tailed mealybugs (Pseudococcus longispinus (Targioni-Tozzetti)) on potted citrus plants, and two species of native mealybugs on potted native trees, were placed in pairs in an orchard and a native forest block 500 m away. Sentinel P. longispinus on citrus plants were also placed along transects anchored in each habitat and extending towards the other by 100–150 m. Parasitoids were reared from the retrieved mealybugs. P. longispinus in the orchard was regularly parasitized by four species of exotic Encyrtidae, but was never parasitized by them in the native forest even though the parasitoids were present in the surrounding environment. Sentinel native mealybugs were not parasitized by any species in either habitat, although native parasitoids (especially Errolium sp. (Hym: Platygastridae) and unidentified Hym: Aphelinidae) were collected from native mealybugs within the native forest.