By Jacob Bunge

CHICAGO--Grain and oilseed futures sank after concerns over demand for U.S. crops snapped soybeans' winning streak in agricultural markets.

Corn futures led the decline, falling 3.4% in Tuesday's session, while soybeans ended a seven-day run-up and wheat contracts also fell.

Strength in the U.S. dollar, which can make the country's crops less competitive on international markets, and sliding crude oil futures prices cast a pall over agricultural markets.

The contracts also struggled against concerns that demand for U.S.-grown grain and soybeans could slacken as South American farmers ready for another big harvest, and poultry producers in Asia grapple with avian influenza outbreaks that could cut into bird production and demand for feed.

Some analysts saw soybeans due for a correction after a seven-day rally that boosted January-dated contract price by 7.1%, amid worries that demand from some reliable overseas buyers like China began to wane. Strong overseas demand had driven much of the upswing, but Brazil and Argentina are expected to ramp up exports soon, ratcheting up competition to U.S. oilseeds.

"We're just seeing a good selloff after several days of a run-up in beans," said Terry Reilly, senior commodity analyst for Futures International in Chicago.

January-dated contracts settled 1.3% lower at $10.42 1/2 a bushel.

Corn futures expiring in December lost 11 3/4 cents a bushel to close at $3.36 3/4 a bushel, the lowest settlement price in two months, pressured by concerns over broader bird flu outbreaks. Japanese authorities plan to destroy more than 300,000 chickens and ducks in response to an outbreak there, local media reported early Tuesday, following similar steps in South Korea, Germany, the Netherlands and Sweden.

Culling overseas flocks could boost U.S. poultry exporters, but grain-market analysts said it could also cut into demand for U.S.-produced feed grain, contributing to corn's slide Tuesday.

Strength in the U.S. dollar was seen factoring into a 1.4% decline in December-dated Chicago wheat contracts, which settled lower for the fifth straight session. The contracts have lost 6.4% over that period.

Write to Jacob Bunge at jacob.bunge@wsj.com

(END) Dow Jones Newswires

November 29, 2016 15:37 ET (20:37 GMT)

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