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Green vegetable bug, Nezara viridula, in pecans

Pecan orchard
Green vegie bug on immature pecan nut
parasitic fly Trichopoda giacomellii

Green vegetable bug (GVB) is a pest of a wide range of crops and ornamental plants. The owners of a pecan orchard near Moree, north western New South Wales wanted to reduce their use of pesticides so CSIRO Entomology, amongst other things, looked for possible biocontrol agents.

Pecans are a nut tree native to the southern USA. Feeding of adult GVB causes pre-mature nut fall and black pitting of the kernel.

In 1994, the parasitic fly Trichopoda giacomellii, was imported for quarantine evaluation and subsequently approved for release in Australia in 1996. It is native to South America where it is an important natural enemy of GVB.

T. giacomellii has caused a three to five fold reduction in GVB numbers and the bug is no longer considered a pest at the pecan orchard. When the eggs hatch, the larvae penetrate the body wall and feed in the abdomen.


Supported by: Stahmann Farms, Horticultural Australia Ltd

parasitised green vegie bug