By Jesse Newman

CHICAGO--Grain and soybean futures slumped on Monday, weighed down by broad selling across agricultural markets and growing optimism over South American crops.

Soybean prices slid to the lowest level in more than two-weeks as speculation grew that improving weather conditions in Argentina would benefit crop yields in that country, resulting in a bigger-than-anticipated harvest. Although rains swamped farm fields in Argentina earlier this month, drier weather has since set in, providing a boost to maturing crops. That's quelling hopes that production problems in South America would translate into increased demand for U.S. supplies.

Lower prices for the oilseeds also came as large investors liquidated bullish bets on soybeans amid renewed concerns over stiff competition from key U.S. rivals in the global market.

Soybean futures for March delivery fell 26 1/2 cents, or 2.5%, to $10.22 3/4 a bushel at the Chicago Board of Trade, the lowest settlement price since Jan. 11.

Corn prices also declined to a more than two-week low, despite evidence of ongoing demand for U.S. supplies of the grain. The U.S. Department of Agriculture on Monday said private exporters had booked sales of 105,000 metric tons of corn for delivery to Colombia during the 2016-17 season.

Still, some traders dissolved bets on higher corn prices after federal data last week showed speculative investors now are holding a net-long position in the corn market, a sign that many factors favorable to corn prices have been priced in and the market may not move higher in the short term.

CBOT March corn declined 4 3/4 cents, or 1.3%, to $3.57 3/4 a bushel, the lowest closing price since Jan. 11.

CBOT March wheat fell 6 1/2 cents, or 1.6%, to $4.14 a bushel, the lowest settlement price since Jan. 3.

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

(END) Dow Jones Newswires

January 30, 2017 16:21 ET (21:21 GMT)

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