SINGAPORE - Chicago corn futures slid to a one-week low on Thursday, falling for a third consecutive session, as prices were pressured by fund selling although planting delays provided a floor under the market.

Wheat and soybean futures lost ground. 

The most-active corn contract on the Chicago Board Of Trade gave up 0.3% at $4.39-1/2 a bushel by 0229 GMT, having dropped earlier in the session to its lowest since June 13 at $4.36-1/2 a bushel.

Wheat was down 0.6% at $5.19-1/4 a bushel, having closed down 1.7% on Wednesday and soybeans lost 0.5% to $8.98-1/2, adding to Wednesday's losses of 1.1%.

"It seems the corn market is putting in a strong case for having reached a peak for now," said Tobin Gorey, director of agricultural strategy at Commonwealth Bank of Australia.

"The U.S. corn crop is going to be substantially smaller in season 2019. Nonetheless the drop does not leave supply tight, it just loses comfort."

Heavy rains across the Midwest threaten to delay planting of both corn and soybeans.

Both crops are lagging well behind historical average levels, but the biggest concern centres around corn, which has an earlier planting window.

Commodity funds were net sellers of CBOT corn, soybean, wheat and soymeal futures contracts on Wednesday and net buyers of soyoil, traders said.

Heavy storms that have hit eastern Argentina over the past few days will cause delays in planting of next season's wheat crop, but they could also help farmers grow more of the grain thanks to replenished water reserves, weather experts said.

Argentina, one of the world's major grain exporters, has been benefiting recently from adverse weather hitting U.S. wheat crops, with the local exchange estimating record wheat production in the 2019/20 season.

Egypt's state grains buyer purchased 290,000 tonnes of wheat in an international tender. It bought 110,000 tonnes of Russian and 180,000 tonnes of Romanian wheat.   

(Reporting by Naveen Thukral; editing by Uttaresh.V)

© Reuters News 2019