By Jesse Newman

CHICAGO--Grain and soybean futures fell Tuesday as selling picked up in agricultural markets amid generous crop supplies.

Soybean prices led the declines, sliding back below the psychologically significant $10 per bushel level thanks to lower prices for products made from the crop and speculation the government could boost its forecast for U.S. production.

Prices for the oilseeds improved steadily in October, but U.S. growers are widely expected to make good harvest progress in coming days, likely wrapping up fieldwork by the end of the week. Meanwhile, yield reports from farmers' fields have been stellar this year, and speculation is growing that the U.S. Department of Agriculture, ina monthly report due out next Wednesday, may raise its forecast for domestic output of the crop, which already is seen at record levels.

"The trade is focusing on supply which looks to be huge," said Brian Hoops, president of Midwest Market Solutions Inc., a commodity-market advisory and brokerage firm in Springfield, Mo.

Lower prices for soybean meal and soyoil also pressured the soybean market. Prices for soyoil, which is used in cooking and fuel, have been leaking lower since notching a more than 2-year high last week, as worries subside somewhat over tight world supplies of vegetable oils like palm and soy. Prices for soybean meal, an animal feed ingredient, fell 2.1% on Tuesday.

Soybean futures for November dropped 18 cents, or 1.8%, to $9.84 1/4 a bushel at the Chicago Board of Trade.

Corn prices declined for a third consecutive session as the U.S. harvest advanced, with just one-quarter of the crop left to be collected, according to the government. Federal forecasters have predicted farmers will reap a record U.S. corn crop this year, which is expected to add to the largest global grain supplies ever this season.

CBOT December corn futures dropped 5 3/4 cents, or 1.6%, to $3.49 a bushel.

Wheat prices also closed lower, pressured by weaker corn and soybean prices and huge domestic and world inventories of the grain. Still, losses in the market were capped by reports that 15% of Australia's wheat crop had been damaged by a recent frost, which could result in lower production and a boost in demand for U.S. wheat exports.

CBOT December wheat declined 2 cents, or 0.5%, to $4.14 1/4 a bushel.

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

(END) Dow Jones Newswires

November 01, 2016 15:55 ET (19:55 GMT)

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