Using the Sterile Insect Technique Against the Bagrada Bug

To combat the spread of the invasive stinkbug, Bagrada hilaris, commonly known as the Bagrada bug, on several economically important plants in the Brassicaceae cabbage family in the United States, the European Biological Control Laboratory (EBCL) staff and partners are developing environmentally compatible biological control strategies.

These include the use of host-specific egg parasitoid species like Gryon gonikopalense, a parasitoid of the Bagrada bug (read the full study here). In addition, the team is also conducting investigations on the applicability of using the Sterile Insect Technique (SIT) where Bagrada bug individuals are sterilized using irradiation and then released into the environment to reduce its host’s population levels.

Individuals used in the evaluation of the SIT were collected from the remote Mediterranean island of Pantelleria in Southern Italy, where the Bagrada bug is present and impacting caper plants. The current work evaluated the impact of irradiation on eggs, and both genders of the Bagrada bug at nine different doses, ranging from 16 Gray to 140 Gray.

Life history parameters such as longevity, fertility and fecundity were evaluated, and the success of parasitism by the Gryon species exposed to irradiated eggs. The team plans to test the suitability of using a SIT program to control the Bagrada bug, at first on this island, and secondly in the United States and beyond. This work is still ongoing but provides very promising insights into the control of this and potentially other stinkbug species.

Authors: René FH Sforza and Massimo Cristofaro

Contact: Michael Grodowitz

The European Biological Control Laboratory (EBCL) was established in 1991 near Montpellier, France. EBCL was created by the merger of the former European Parasite Laboratory, established in Paris in 1919, and the Biological Control of Weeds Laboratory in Rome. EBCL has a satellite laboratory in Thessaloniki, Greece. As the only USDA ARS-operated laboratory outside the United States, EBCL develops biological control technologies which can be used to suppress invading weeds and insect pests of Eurasian origin. EBCL researchers do this by searching for natural enemies (insects, mites, and pathogens) in their native habitat, determining their identity, testing their host specificity and potential impact in laboratory and field experiments, and shipping promising organisms to the U.S. for further testing as biological control agents. EBCL collaborates with scientists in many countries in Europe, Asia, and Africa to explore in regions of origin of the target weeds and insects.