Natural tick control tested

January 13, 2011 By Jan Suszkiw
Natural tick control tested
Lignin-encapsulated (LE) nootkatone, a component of essential oil in grapefruit peels and other sources, has been found to be a good repellent against ticks that transmit Lyme disease.

Nootkatone, a component of essential oil in grapefruit peels and other sources, is used in many food, beverage and personal-care products because of its clean, citrusy taste and smell.

Now, nootkatone may find another use: repelling blacklegged deer ticks that spread Lyme disease. U.S. Department of Agriculture (USDA) entomologist Bob Behle is investigating the possibility with Kirby Stafford, an entomologist at the Connecticut Agricultural Experiment Station (CAES) in New Haven, Conn.

Stafford began researching nootkatone's tick repellency in 2008 and sought Behle's formulation expertise when it became apparent the essential oil lacked sufficient residual activity to kill the tick's tiny nymph stage, which is more likely to transmit the Lyme disease bacterium than the larger, easier-to-spot adults.

In studies at the Crop Bioprotection Research Unit, operated in Peoria, Ill., by the Agricultural Research Service (ARS), Behle and colleagues refined a spray-dry procedure that uses lignin to encapsulate the nootkatone. ARS is USDA's principal intramural scientific research agency.

In nature, lignin acts like a molecular mortar that binds . In this instance, the lignin served as semipermeable packaging that extended nootkatone's residual activity and improved its effectiveness.

In greenhouse tests, the lignin-encapsulated (LE) nootkatone lasted longer than a previously tried formulation, known as emulsified concentrate (EC), and caused less harm (phytotoxicity) to cabbage plants when applied at standard field rates. No signs of plant damage were observed when researchers applied the LE formulation in outdoor trials, conducted in 2009 on residential properties. Just as importantly, no live ticks were recovered from treated sites.

Another round of tests was conducted this past June on nine residential properties—five of them using another nootkatone-encapsulating formulation devised by Behle.

In 2009, the U.S. Centers for Disease Control and Prevention reported 29,959 confirmed cases of , which can affect the joints, heart and nervous system of afflicted individuals if left untreated.

Explore further: Rhode Island deer tick effort under way

More information: Read more about the research in the January 2011 issue of Agricultural Research magazine.

Related Stories

Rhode Island deer tick effort under way

November 4, 2005

Thirty tick-killing bait stations have been deployed in Rhode Island for what's believed to be the largest tick control project in the nation.

Getting rid of cattle fever ticks

November 2, 2010

Scientists at the U.S. Department of Agriculture (USDA) have developed two strategies to ward off cattle fever ticks that are crossing the border from Mexico into the United States. These ticks transmit bovine babesiosis, ...

Recommended for you

How bees naturally vaccinate their babies

July 31, 2015

When it comes to vaccinating their babies, bees don't have a choice—they naturally immunize their offspring against specific diseases found in their environments. And now for the first time, scientists have discovered how ...

Researchers design first artificial ribosome

July 29, 2015

Researchers at the University of Illinois at Chicago and Northwestern University have engineered a tethered ribosome that works nearly as well as the authentic cellular component, or organelle, that produces all the proteins ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.