This review draws together available information on the biology, methods for study, and culturing of hymenopteran parasitoids of the Queensland fruit fly, Bactrocera tryoni, and assesses prospects for improving biological control of this serious pest. Augmentative release of the native and naturalised Australian parasitoids, especially the braconid Diachasmimorpha tryoni, may result in better management of B. tryoni in some parts of Australia. Mass releases are an especially attractive option for areas of inland eastern Australia around the Fruit Fly Exclusion Zone that produces B. tryoni-free fruits for export. Diachasmimorpha tryoni has been successful in other locations such as Hawaii for the biological control of other fruit fly species. Biological control could contribute to local eradication of isolated outbreaks and more general suppression and/or eradication of the B. tryoni population in endemic areas. Combining biological control with the use of sterile insect technique offers scope for synergy because the former is most effective at high pest densities and the latter most economical when the pest becomes scarce. Recommendations are made on methods for culturing and study of four B. tryoni parasitoids present in Australia along with research priorities for optimising augmentative biological control of B. tryoni.

Augmentative releases of parasitic wasps may improve management of the Queensland fruit fly, Bactrocera tryoni Froggatt, in inland New South Wales (NSW). A survey was conducted from October 2008 to April 2009 to detect the presence of parasitoids of fruit fly. Fruit fly‐infested fruits were collected in Wagga Wagga, Cootamundra, Ganmain, Gundagai, Lockhart and Lake Cargelligo on the south‐west slopes and plains of NSW and Albury‐Wodonga on the NSW‐Victorian border. Two species of opiine parasitoids were detected: Diachasmimorpha kraussii (Fullaway) and D. tryoni (Cameron); both species from fruits that also yielded B. tryoni and island fruit fly, Dirioxa pornia (Walker). Nine per cent of fruit samples yielded parasitoids. There were statistically significant differences between fruit type, fruit species, sampling events and towns. Fruit fly parasitoids were most commonly detected in fig (27.2% of samples), followed by stone fruit (11.5%), pome fruit (6.1%), loquat (4.3%) and citrus (2.1%). Parasitoid incidence varied throughout the fruit fly season, peaking in February–March 2009 (17.4%). Of the towns surveyed, Cootamundra had the highest incidence of parasitoids (28.8%), followed by Wagga Wagga (9.5%), Gundagai (10.2%) and Lockhart (1.2%), with no parasitoids detected in Albury‐Wodonga, Ganmain or Lake Cargelligo. Diachasmimorpha tryoni was detected in all surveys except January–February 2009, during a heatwave. Diachasmimorpha tryoni was most prevalent in November–December 2008 (5.2%). Diachasmimorpha kraussii was most prevalent in February–March 2009 (14.5%), but was not detected in October 2008 or April 2009. Diachasmimorpha tryoni was detected in Wagga Wagga (6.1%) and Cootamundra (1.9%), with D. kraussii detected in Wagga Wagga (9.5%), Cootamundra (26.9%), Gundagai (10.2%) and Lockhart (1.2%). The presence of these parasitoid species in the region suggests they may be suitable for augmentative release in the control of B. tryoni in inland NSW.

Current sampling protocols for pest whitefly in greenhouse cropping systems are not adequate for detection of Bemisia tabaci when it is part of a mixed species population. Greenhouse vegetable and flower crops in the north, west and south of Sydney were sampled for fourth-instar whitefly nymphs in autumn, winter and spring of 2007. Bemisia tabaci was found in all regions: in the north in winter, the west in all seasons and the south in autumn and winter. A comparison of a Poisson model for pest abundance and a binomial model of presence/absence showed the same factors to be significant, indicating that it is sufficient to sample for presence/absence of the pest on individual plants, rather than to measure pest abundance per plant. A model using the binomial distribution determined that if more than 20% of plants are infested with B. tabaci, a sample size of 20 whole plants per greenhouse is sufficient to detect the presence of B. tabaci with greater than 95% confidence.a en_819 276..280