Every year, millions of dollars go towards safeguarding wood against its six-legged nemesis — the termite. Although usually associated with southern United States, research has shown that these wood-munching insects can infect wood as far north as Wisconsin. Among the chemical sprays and concrete barriers used to combat termites are an array of copper-based, anti-termite wood preservatives.
Unfortunately, in addition being bad for termites, the copper in these preservatives may also be detrimental to the environment. Some researchers have posited that copper-treated wood may also be linked to the destabilization and premature failure of metal fasteners. Environmentally and structurally safe alternatives (that can meet the demands of green construction) are becoming high on the eco-friendly consumer’s priority list.
When formulating these new treatments, researchers at the Forest Products Laboratory (FPL) may need to enlist the help of another ten-legged animal — the shrimp. Chitosan, a compound known to deter wood decay fungi and some species of insects, can be synthesized from chitin, a waste product generated during industrial shrimp processing. In addition to being environmentally friendly, production of this “shrimp cocktail” is relatively inexpensive.
Although chitosan’s effectiveness against termites is currently unknown, a new FPL study, in cooperation with Mississippi State University, hopes to find out just how much chitosan-laden wood termites can handle. After determining how the insects react to different concentrations of compound, researchers will see if the termites adapt to the chitosan, and if they do, attempt to uncover the biological processes underlying these adaptations. This in-depth evaluation will even include studying the DNA and RNA profiles of the termite digestive tract.
The termite gut can contain 10 million to 1 billion microbes per termite. Recent studies have shown that a termite’s diet can influence the composition of this microbe community and the termite’s wood-degrading enzymes. By analyzing the genetic profiles of the microbes as the termites consume the chitosan, researchers hope to better understand expression of protein(s) or protein product(s) that are responsible for any resistance to the compound.
In addition to verifying the utility of chitosan as a termiticide, the 5-year-long project will offer insight into other aspects of wood preservation. The genetic profiles alone will provide future studies with a wealth of knowledge, and shed more light onto the mechanism of wood degradation by termites.
The information could also be used to improve current approaches to wood protection, further our overall understanding of wood conversion to energy, and may assist in the development of future value-added products.
For more information, please see the Research in Progress publication Effect of Chitosan on the Termite Digestome.