Formosan subterranean termites control

Since this symposium was held in New Orleans, it was appropriate to describe research aimed at efficient control of the Formosan subterranean termite (Coptotermes formosanus). The Formosan subterranean termite is among the most devastating urban pests in the world wherever it has spread. Its management costs the U.S. alone hundreds of millions of dollars a year. 

Assessment of Natural Products for Control of Formosan Subterranean Termites... 

Numerous plant species have been reported to be resistant to attack from subterranean termites. Many of these plants and extracts derived from them were tested for leads as potential natural product basexl pesticides. Forty plant and tree extracts reported to be active against termites displayed poor activity against the Formosan subterranean termite at rates < 0.5% wt/wt. Most naphthoquinones were active with a non-polar substitution in the 2-position. Anthroquinones generally had little termiticidal activity. None of the plant extracts or natural products tested were sufficiently active to be considered useful for control of the Formosan subterranean termite without structural modification. 

In the middle of the 20th century, the synthetic development of DDT and other chlorinated hydrocarbons (C.H.), increased insecticidal activity well beyond that of most natural products. Problems arose with bioaccumulation of C.H. residues in the food chain, human fat tissue, mother s milk, as well as the development of insecticide resistance. It became obvious there were limitations to synthetic technology as well. The modification of a natural product, for example, from chrysanthemum flowers and their pyrethrum extracts (7) to pyrethroids such as allethrin, resmethrin, permethrin (2), and deltamethrin created a model in which insecticides are created from the skeleton of insecticidally active natural molecules. Thus, the avermectin, abamectin, ivermectin family of pesticides originated from compounds produced by the soil bacterium, Streptomyces avermitilis (5), and the commercially successful chloronicotinyl insecticides, though not derived from nicotine, are chemically related 4). Both pyrethroids and chloronicotinyls are currently used commercially as termiticides. We have previously provided a detailed review of natural products as pesticidal agents for control of the Formosan subterranean termites, Coptotermes formosanus Shiraki (5). 

The purpose of this research was to determine whether various plants or woods and their extracts had an efrect on Formosan subterranean termites to warrant further evaluation for termite control applications. Based on activity of wood extracts, an extensive series of substituted quinones was evaluated to gain insight into the relationship of substitutions to termiticidal activity for synthesis of more active compounds. 

As a liquid termiticide, fipronil provides long-term (>10 years) control of many urban termite species [113]. It is not detected in the soil by termites [114, 115] and its relatively slow action against both subterranean Reticulitermes Jlavus) and Formosan termites Coptotermes formosanus) [116] allows transfer, through several routes, to other members of the colony, leading to colony elimination [117]. 

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