March 21 (Bloomberg) -- Cotton futures fell to a one-week low on signs that farmers will plant more of the crop than expected in the U.S., the worldΆs biggest exporter.

U.S. cotton seeding may total 11 million acres, 10 percent more than a Feb. 22 government forecast of 10 million, said Jordan Lea, the chairman of Eastern Trading Co., an exporter in Greenville, South Carolina. Farmers are boosting output as prices head for a fifth monthly gain, the longest rally since July 2009.

“Talks that farmers may look to take advantage of higher pricing and plant more than expected cotton has weighed on our market,” Michael Sweeney, a senior cotton broker at Marex Spectron in New York, said in an e-mail.

Cotton for May delivery slumped 1 percent to settle at 88.2 cents a pound at 2:30 p.m. on ICE Futures U.S. in New York, after touching 87.96 cents, the lowest since March 13. Prices are down 6.1 percent since reaching an 11-month high on March 15.

Prices also fell today on speculation that China will sell fiber from state reserves, Sweeney said. Government inventories are set to climb to about 9 million metric tons by the end of March, according to Kuang Bo, an analyst at Yongan Futures Co.

The Asian country, the worldΆs biggest consumer, imported 378,800 tons of cotton in February, down 39 percent from last year and 17 percent lower than the 457,500 in January, according to a government report today.