Submitted to: Biocontrol Science and Technology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 10/1/2008
Publication Date: 2/1/2009
Citation: Toepfer, S., Haye, T., Erlandson, M., Goettel, M., Lundgren, J.G., Kleespis, R.G., Weber, D.C., Cabrera-Walsh, G., Jackson, J.J., Peters, A., Vidal, S., Strasser, H., Ehlers, R.V., Moore, D., Keller, S., Kuhlmann, V. 2009. A Review of the Natural Enemies of Beetles in the Subtribe Diabroticina (Coleoptera: Chrysomelidae): Implications for Sustainable Pest Management. Biocontrol Science and Technology. 19(1): 1-65. Interpretive Summary: Rootworms are some of the world’s more severe agronomic pests, but there have been relatively few concerted efforts to understand the biotic mortality factors responsible for regulating rootworm (and other Diabroticine beetle) populations. This paper represents an international effort to summarize the state of knowledge concerning natural enemies of rootworms, bean leaf beetles, and cucumber beetles. The major outcomes of the review are 1) several natural enemies, especially nematodes, hold promise for use as augmentative biological control agents, 2) the areas where these pests originated, and where natural enemies have coevolved with the pests, are under-explored for potential classical biological control agents, and 3) cultural management practices designed to manipulate endemic populations of natural enemies has potential for reducing grower’s reliance on chemical pesticides for this pest. By synthesizing current knowledge on this topic, biological control of rootworms and other Diabroticine pests is more attainable by practitioners.
Technical Abstract: Diabroticina is a speciose subtribe of New World Chrysomelidae (Subfamily Galerucinae: Tribe Luperini) that includes pests like corn rootworms, cucumber beetles and bean leaf beetles (e.g. Diabrotica, Acalymma, Cerotoma species). The evolution and spread of pesticide resistance, the European invasion of Diabrotica v. virgifera LeConte, and possible development of resistance due to the large-scale deployment of Diabrotica-active Bt maize in North America have generated a sense of urgency in developing biological control options against Diabroticina pests. In the present study, we review available knowledge on biological control options, including 290 publications on natural enemy–Diabroticina associations in the New World. Several natural enemy species or groups appear to be promising candidates for control strategies with different ecological rationales. We propose that future research should pursue: (1) development of inundative biological control products, particularly mass-produced entomopathogenic nematodes and fungi, (2) understanding of specific natural enemies of Diabroticina larvae throughout the Americas and of adults particularly in higher altitudes of Central America or northern South America including potential classical biological control agents against D. v. virgifera; (3) enhancement of natural enemies through cultural practices, i.e.: reduced tillage, reduced weed control, cover crops, diversified crop rotations or soil amendments. Research and action must be coordinated to accelerate the exploration of biological control options, which may provide urgently-needed advances in insect pest management.