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ARS Home » Southeast Area » Fort Lauderdale, Florida » Invasive Plant Research Laboratory » Research » Publications at this Location » Publication #432729
Research Project: Development and Implementation of Biological Control Programs for Natural Area Weeds in the Southeastern United States

Location: Invasive Plant Research Laboratory

Title: Are the air potato beetles Lilioceris egena & L. cheni synergistic?

Author
item Dray Jr, Forrest
item Leidi, Jorge
item FOSTER, BRIANA - University Of Florida
item Halbritter, Dale
item RAYAMAJHI, MIN - Retired ARS Employee

Submitted to: International Symposium on Biological Control of Weeds
Publication Type: Abstract Only
Publication Acceptance Date: 2/20/2026
Publication Date: 3/9/2026
Citation: Dray Jr, F.A., Leidi, J.G., Foster, B.M., Halbritter, D.A., Rayamajhi, M.B. 2026. Are the air potato beetles Lilioceris egena & L. cheni synergistic?. International Symposium on Biological Control of Weeds. 1-3.

Interpretive Summary: Lilioceris egena is an Asian beetle recently released to combat the invasive air potato vine. It preferentially damages the air potato bulbils, which is the primary means of reproduction for this plant. A second beetle, Lilioceris cheni, was released against this vine in 2011 and extensively damages the leaves. This current study investigates the effects of the two beetles acting together at the same time on the vines in a controlled setting (cages in the field). Preliminary analysis shows mixed results, with evidence of improved control overall but also possible interference between the two species.

Technical Abstract: Dioscorea bulbifera (air potato) is an invasive vine that transforms ecosystems by smothering and outcompeting native plant species. It colonizes new sites by means of tuber-like reproductive structures called bulbils, which develop above ground in the leaf axils. Air potato bulbils appear on air potato vines in the late summer months and dehisce by winter. Bulbils produce new vines, as well as persistent underground tubers, during the following spring. Two classical biological control agents, both beetles in the genus Lilioceris, have been introduced from the vine’s native range to help combat its spread. The air potato leaf beetle (APLB), L. cheni, was first released in Florida in late 2011. APLB adults and larvae feed on air potato foliage where adults also oviposit. The second beetle, the air potato bulbil beetle (APBB), L. egena, was first released in Florida in late 2021. APBB adults and larvae preferentially feed by burrowing into the bulbils, with adults ovipositing on the exterior of the bulbil at the soil surface or within adult feeding tunnels inside the bulbil. Both species pupate in the soil, though APBB will also occasionally pupate inside a bulbil. Differences in feeding habits by the two species prompted the question of whether they would work synergistically in damaging the vine. We examined this question by setting up a dozen cages containing two vines each. We set up four treatments of three cages each, containing either no beetles, only APLB, only APBB, or both APLB and APBB. Beetles remained in the cages for two months after which we harvested the experiment. Preliminary analysis shows mixed results in terms of foliar damage and bulbil damage. We discuss the implications of this outcome in terms of air potato management efforts.