Establishment in Australia of Trichopoda giacomellii (Blanchard) (Diptera: Tachinidae), a biological control agent for Nezara viridula (L.) (Hemiptera: Pentatomidae)
Releases of Trichopoda giacomellii (Blanchard) for biological control of Nezara viridula (L.) took place at sites in western New South Wales and south-eastern Queensland between 1996 and 1999. Trichopoda giacomellii became established near Moree in north-western New South Wales, whereas establishment at sites near Brisbane has not been confirmed. Releases of adult T. giacomellii and of parasitised N. viridula were made either directly onto host plants (1996 and 1997) or following temporary confinement in a field cage (1998 and 1999). Parasitism of N. viridula adults by T. giacomellii ranged from 9 to 72% between January 1999 and February 2000, and was 42% of adults during diapause. The methods employed to establish T. giacomellii in this study are compared with other attempts to establish Trichopoda spp. elsewhere in the world. Release methodologies that limit immediate dispersal of the agent and/or their progeny are recommended for establishing Trichopoda spp.