By Ilan Brat

CHICAGO--U.S. soybean futures fell Friday on concerns that the oilseeds have lost some international competitiveness after China canceled an import order.

Corn finished lower and wheat was mixed.

Soybeans came under selling pressure throughout the session following a U.S. Department of Agriculture report indicating that China had cancelled an order for 200,000 metric tons. Ample production in South America is competing with U.S. output, weighing on prices and raising concerns about the international competitiveness of U.S. oilseed supplies. Brazil's currency, the real, weakened versus the dollar on Friday, supporting the global attractiveness of Brazilian soybeans.

The weakened Brazilian real "gives the exports out of Brazil a competitive advantage," said Michael McDougall, director of agricultural commodities for Societe Generale.

Chicago Board of Trade soybean futures for August delivery fell 9 1/2 cents, or 1%, to $9.80 3/4 a bushel.

Corn oscillated between gains and losses during the session and ultimately closed lower. Analysts said a USDA report of an export order to Mexico helped bolster prices but uncertainty about whether an extremely rainy June and early July and a subsequent spell of benign weather would make output more or less than expected added some pressure.

CBOT corn futures for September delivery ended 2 1/4 cents, or 0.6%, lower at $3.71 a bushel.

Wheat settled mixed. A decline in the dollar supported prices.

A weaker greenback helps make U.S. supplies more affordable for foreign buyers. The overall strength of the dollar in the last year has battered grains and soybeans in general and dragged particularly on wheat, one of the most global of grains. It has helped make European and Russian wheat more attractive to big buyers such as Egypt and relegated U.S. supplies to a position farther down buyers' preferences list.

At the same time, some private estimates during the week for strong wheat yields weighed on prices.

CBOT wheat futures for September delivery were up 2 3/4 cents, or 0.6%, to $4.99 1/4 a bushel. CBOT March 2016 wheat was 3/4 cent, or 0.2%, lower at $5.10 1/2 a bushel.

Write to Ilan Brat at ilan.brat@wsj.com

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