GRAINS-Wheat rallies as Russia threatens to quit Black Sea grains deal


Wheat jumps on worries about Black Sea shipments


Corn, soybeans pare losses as wheat gains


Supply worries underpin grains

(Adds closing prices)

CHICAGO, Oct 13 (Reuters) - U.S. wheat futures rebounded on Thursday from two days of declines on concerns that a Black Sea export corridor deal may not be renewed next month, which could again disrupt grain shipments from Ukraine.

Corn and soybeans pared earlier losses on spillover support from wheat and follow-through buying after the U.S. Department of Agriculture (USDA) lowered its U.S. harvest outlook for both crops the previous day.

A weaker dollar, which makes U.S. shipments more attractive to importers holding other currencies, offered additional support to grains.

Wheat surged on news that Russia delivered a list of concerns about its Black Sea export corridor deal to the United Nations and is prepared to reject renewal of the deal next month.

The UN-brokered deal had opened a safer path for grain shipments from major exporter Ukraine. Exports had been blocked following Russian President Vladimir Putin’s order to invade its neighbour in late February.

“This is the Putin effect. It looks like it’s not going to be so easy to keep that export corridor open,” said Don Roose, president of U.S. Commodities.

Chicago Board of Trade December wheat futures settled up 10 cents at $8.92-1/4 a bushel after hitting a two-week low earlier in the session.

CBOT December corn was up 4-3/4 cents at $6.97-3/4 a bushel while November soybeans were down a 1/4 cent at $13.95-3/4 a bushel.

In its monthly supply-and-demand report on Wednesday, the USDA said U.S. corn and soybean crops would be smaller than previously forecast, raising concerns about tight global inventories. But the agency also trimmed its demand outlook, most notably for exports which will likely face stiff competition from South American crop shipments.

The government also cut its outlook for the domestic stockpile of wheat to the lowest in 15 years. (Additional reporting by Naveen Thukral in Singapore and Sybille de La Hamaide in Paris; Editing by Marguerita Choy and Grant McCool)