Non-selective feeding and oviposition behaviour of Cryptocephalus trifasciata (Coleoptera: Cerambycidae: Cryptocephalinae) precludes its use as a biological control agent for downy rose myrtle (Rhodomyrtustomentosa)^*

* Case-bearing beetle is not suitable as biological control for Rhodomyrtus tomentosa.

ABSTRACT

Downy rose myrtle (Rhodomyrtus tomentosa), a southeast Asian native shrub, invades natural areas in Florida and Hawaii, where it forms dense, impenetrable thickets. We tested the host affinity and survivorship of a case-bearing beetle, Cryptocephalus trifasciata on R. tomentosa and related species. C. trifasciata adults and larvae fed, oviposited and/or completed development on all non-target species tested (N = 11). C. trifasciata has a broad host range and is unsuitable for use as a biological control agent.

KEYWORDS:

• Biological control of weeds
• downy rose myrtle
• host-specificity testing
• Myrtaceae
• case-bearing beetle

Acknowledgements

Susan Wright, Chris Souders, Jamie Lollis, Esteban Peralta and Dehlia Albrecht (USDA-ARS, Gainesville) provided much of the support for establishing rearing protocols for the insects, for growing the plant material and for gathering much of the data. Matthew Purcell (CSIRO) assisted tremendously with obtaining and packing collections from Hong Kong. Mention of trade names or commercial products in this publication is solely for the purpose of providing specific information and does not imply recommendation or endorsement by the US Department of Agriculture (USDA). USDA is an equal opportunity employer and provider.

Disclosure statement

No potential conflict of interest was reported by the authors.

Notes

* Case-bearing beetle is not suitable as biological control for Rhodomyrtus tomentosa.

Additional information

Funding

This research was supported, in part, by support through grants from the South Florida Water Management District and the Florida Fish and Wildlife Conservation Commission.