By Jesse Newman

CHICAGO-Grain and soybean futures dropped to fresh lows Friday, extending losses in agricultural markets following quiet trade ahead of the Christmas holiday.

Soybean prices declined to a more than five-week low, buffeted by forecasts for more crop-friendly rains in Argentina, which have helped alleviate fears that dry weather would dent production in that country. Weather forecasts call for rains in northern Argentina and across most of Brazil, boosting South American growing conditions and spurring speculation that farmers there will see strong soybean harvests, which could increase competition for U.S. exports.

"The weight of the South American harvests keeps beans under pressure," said Charlie Sernatinger, head of grain trading at ED&F Man Capital Markets in Chicago.

Prices for the oilseeds sank nearly 5% for the week, prompting traders to weigh whether the market is in for a prolonged slide that erases an earlier autumn rally. Although demand for U.S. soybean supplies has been robust so far this season, foreign purchases are expected to drop off in the new year as freshly-harvested South American rations come online, potentially depressing the market further.

Soybean futures for January fell 5 1/2 cents, or 0.6%, to $9.89 a bushel at the Chicago Board of Trade, the lowest closing price since Nov. 16.

Corn prices drifted to a three-week low after trading in a narrow range on Friday. Losses in that market totaled nearly 3% for the week, as prices were weighed down by massive domestic and world supplies and a strong U.S. dollar, which is unfriendly for U.S. farm exports.

The dollar notched a fresh13-year high against a basket of international currencies earlier in the week.

CBOT March corn futures slipped 1 1/2 cents, or 0.4%, to $3.45 3/4 a bushel, the lowest settlement price since Dec. 2.

Wheat futures eased amid light trading volume, with prices for that grain dragged lower by lackluster demand and strong world harvests. Farmers in Australia are harvesting a record wheat crop, which will add to global grain supplies that already are the biggest the world has ever seen. Meanwhile, a firm greenback is making U.S. wheat less competitive on the world market.

CBOT March wheat futures slid 3 1/2 cents, or 0.9%, to $3.93 1/2 a bushel.

Write to Jesse Newman at jesse.newman@wsj.com

(END) Dow Jones Newswires

December 23, 2016 14:35 ET (19:35 GMT)

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