U.S. corn futures rallied Wednesday, rising to one-week highs, fueled by positive technical signals and concerns about delayed crop plantings in South America due to heavy rainfall.

Corn prices bounced back from recent losses, climbing to the top end of a three-week trading range.

Corn futures for December delivery rose 14 cents, or 1.9%, to settle at $7.55 3/4 a bushel at the Chicago Board of Trade.

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Traders pushed corn higher after technical signals showed the market held above closely watched support levels in recent days, said Mike Zuzolo, president of Global Commodity Analytics and Consulting in Lafayette, Indiana.

Prices also got a boost from concerns about a slow start to the planting season in parts of Brazil and Argentina where heavy rainfall is keeping farmers out of their fields. Brazil and Argentina are the world's largest producers after the U.S.

Wheat futures, which often trade in tandem with corn, also rose Wednesday, amid hopes that export demand for U.S. wheat will rise in the coming weeks. Export competition from Europe's Black Sea region is drying up as supplies run low in Ukraine and Russia.

December wheat futures ended up 7 3/4 cents, or 0.9%, to $8.64 1/2 a bushel at the Chicago Board of Trade. Kansas City Board of Trade December wheat rose 1 3/4 cents, or 0.2%, to $9.04 a bushel. MGEX December wheat finished up 7 1/4 cents or 0.8%, at $9.42 a bushel.

U.S. soybean futures settled higher, boosted by strong demand, firm cash prices, and uncertainty over crops in South America.

Chicago Board of Trade soybeans for November delivery settled up 13 1/4 cents or 0.9% at $15.47 a bushel. Soybeans for January delivery finished up 12 1/4 cents or 0.8% to $15.48 3/4.

Write to Andrew Johnson Jr. at andrew.johnsonjr@dowjones.com
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(END) Dow Jones Newswires
October 31, 2012 15:33 ET (19:33 GMT)
DJ U.S. Corn Prices Rally on Technical Moves, South American Rains->copyright