Submitted to: Pest Management Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: December 9, 2005
Publication Date: April 20, 2006
Citation: Meepagala, K.M., Osbrink, W.L., Sturtz, G., Lax, A.R. 2006. Plant derived natural products exhibiting activity against formosan subterranean termites (coptotermes formosanus). Pest Management Science. 62:565-570. Interpretive Summary: The Formosan subterranean is among the most devastating termite pests. This termite most likely invaded North America as a result of disembarkation of wooden military cargo at the port of New Orleans that arrived from Asia during and after World War II. This pest costs hundreds of millions of dollars per year in the United States alone. Over the past two decades organo-chlorines and organo-phosphates, the two prominent classes of termite control agents have been banned due to environmental and human health concerns. In our efforts in search of effective, environmentally friendly, termite control agents we have tested some plant extracts for the control of this pest. Plants are known to have chemicals that protect them from insects, fungi and bacteria. We have postulated that this is one area to explore in order to search for such termite control agents. In the laboratory tests three compounds obtained from plant extracts have shown activity against Formosan subterranean termites. These compounds are vulgarone B (isolated from Artemisia douglasiana), apiol (isolated from Ligusticum hultenii) and cnicin (isolated from Centaurea maculosa; also known as spotted knap weed). Apiol was the fastest acting among the three natural products that were tested with 100% mortality at 11 days after treatment when administered at 1% wt/wt. Vulgarone B showed the same effect at 15 days after treatment under the same conditions. Cnicin was the slowest acting among the three compounds with 81% mortality at day 15.
Technical Abstract: The Formosan subterranean termite, Coptotermes formosanus, is among the most devastating termite pests. Natural products derived from plant extracts were tested in a discovery program for effective, environmentally friendly termite control agents. Among the natural products that were tested, vulgarone B (isolated from Artemisia douglasiana), apiol (isolated from Ligusticum hultenii), and cnicin (isolated from Cenaturea maculosa) exhibited significantly higher mortalities compared to untreated controls in laboratory bioassay. These compounds are present in high levels in the respective plant sources and also possess other biological activities such as phytotoxic and antifungal properties.