Submitted to: Biological Control
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: January 14, 2009
Publication Date: March 15, 2009
Citation: Goolsby, J., Moran, P.J. 2009. Host range of Tetramesa romana Walker (Hymenoptera: Eurytomidae), a potential biological control of giant reed, Arundo donax L. in North America. Biological Control. 49:160-168. Interpretive Summary: The plant-feeding wasp, Tetramesa romana Walker, was evaluated as a potential biological control agent of the invasive reed grass, Arundo donax, in North America. Tests were conducted in U.S. quarantine facilities to determine the host range of this insect. Thirty five species of related grasses such as common river reed, economic grass plants such as sugarcane, and other plants such as pecans and willows were tested to determine if the wasp could feed and develop on these non-target plant species. The wasp reproduced normally on Arundo donax and to a limited extent on Arundo formosana. None of the other non-target species were suitable for the wasp. These results indicate that this wasp is sufficiently host specific to pose no significant risk of damaging non-target plants in North America and is recommended for release as a biological control agent of A. donax.
Technical Abstract: The eurytomid wasp, Tetramesa romana Walker, was evaluated as a potential biological control agent of the invasive reed grass, Arundo donax in North America. No-choice tests and timed behavioral studies were used to determine the fundamental host range of two genotypes of the wasp collected from Granada, Spain and Perpignan, France. Thirty five species, including two genotypes of A. donax and seven ecotypes of Phragmites australis, along with closely related grasses, economic grasses and habitat associates were tested. Complete development of both T. romana genotypes was restricted to A. donax and A. formosana. Fecundity of individual females was significantly greater on the A. donax genotype from Laredo, TX (12.8 ± 3.2) as compared to the genotype from San Juan, TX (3.9 ± 1.0) and A. formosana (0.8 ± 0.4). In behavioral studies, probing was observed on fifteen of the thirty five species but the percentage of time spent probing was significantly greater on A. donax. On non-hosts, T. romana spent significantly more of their time (73-100%) off the plant resting on the cage as compared to (39-53%) when exposed to A. donax. These results indicate that this wasp is sufficiently host specific to pose no significant risk of damaging non-target plants in North America and is recommended for release as a biological control agent of A. donax.