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ARS Home » Southeast Area » Fort Lauderdale, Florida » Invasive Plant Research Laboratory » Research » Publications at this Location » Publication #377804
Research Project: Identification, Evaluation, and Implementation of Biological Control Agents for Invasive Weeds of Southeastern Ecosystems

Location: Invasive Plant Research Laboratory

Title: Proximity to host plant of a congener determines parasitism of a waterhyacinth biological control agent by a native parasitoid

Author
item Goode, Ashley
item Tipping, Philip
item Pokorny, Eileen
item KNOWLES, BRITTANY - Former ARS Employee
item Salinas, Luz
item GETTYS, LYN - University Of Florida

Submitted to: Biological Control
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 11/13/2020
Publication Date: 11/17/2020
Citation: Goode, A.B., Tipping, P.W., Pokorny, E.N., Knowles, B.K., Salinas, L.S., Gettys, L.A. 2020. Proximity to host plant of a congener determines parasitism of a waterhyacinth biological control agent by a native parasitoid. Biological Control. 153. https://doi.org/10.1016/j.biocontrol.2020.104477.
DOI: https://doi.org/10.1016/j.biocontrol.2020.104477

Interpretive Summary: The biological control agent Megamelus scutellaris Berg (Hemiptera: Delphacidae) was released in Florida in 2010 to improve control of the invasive aquatic plant, Pontederia (Eichhornia) crassipes (Mart.) Solms (Commelinales: Pontederiaceae). A native egg parasitoid, Kalopolynema ema (Schauff and Grissell) (Hymenoptera: Mymaridae), was documented utilizing M. scutellaris, potentially limiting its effectiveness as a biological control agent. An experiment to determine if the distance from K. ema’s native host impacted parasitism rate of M. scutellaris was conducted in artificial ponds with naturally occurring populations of the native insect species. Models indicated that parasitism decreased with distance from the native host and with increasing M. scutellaris density. Although parasitism increased with K. ema density, rainfall, and temperature, parasitism was low with over half of the test plants indicating no signs of parasitism on M. scutellaris. The lack of a density dependent response by K. ema suggests it will not interfere with biological control of P. crassipes in Florida.

Technical Abstract: The biological control agent Megamelus scutellaris Berg (Hemiptera: Delphacidae) was released in Florida in 2010 to improve control of the invasive aquatic plant, Pontederia (Eichhornia) crassipes (Mart.) Solms (Commelinales: Pontederiaceae). A native egg parasitoid, Kalopolynema ema (Schauff and Grissell) (Hymenoptera: Mymaridae), was documented utilizing M. scutellaris, potentially limiting its effectiveness as a biological control agent. An experiment to determine if the distance from K. ema’s native host impacted parasitism rate of M. scutellaris was conducted in artificial ponds with naturally occurring populations of the native insect species. Models indicated that parasitism decreased with distance from the native host and with increasing M. scutellaris density. Although parasitism increased with K. ema density, rainfall, and temperature, parasitism was low with over half of the test plants indicating no signs of parasitism on M. scutellaris. The lack of a density dependent response by K. ema suggests it will not interfere with biological control of P. crassipes in Florida.