By Claudia Carpenter

U.S. farmers and traders brought their $5 million campaign to buy cotton to U.K. retailers this week to stop the growing preference for manmade fibers.

Cotton accounted for 38 percent of the retail market last year, down from 44 percent in 2008, with the rest manmade fibers such as polyester, according to the National Cotton Council of America. Cotton prices have dropped 8.7 percent this year after almost tripling in the two years through 2010.

“We expect there to be a rebound in cotton,” Rob Miller, director of global marketing of the Cotton Council International in Washington , said in an interview in London yesterday. “ThereΆs been demand destruction at the retail level for the synthetic fibers.”

The Cotton Council International is part of the National Cotton Council, which has members from Allenberg Cotton Co. to Ecom USA Inc. and Cargill Inc. The cotton program started in March in the U.S. followed by visits in Japan, Korea , Taiwan , Hong Kong, Thailand, Italy, Spain and the U.K. Retailers in Germany are last tomorrow, Miller said.