* Slowing U.S. exports cap gains in Chicago corn futures
* Wheat unmoved, soybeans rises after falling for 3 sessions (Adds details, quotes)
By Naveen Thukral
SINGAPORE, Dec 1 (Reuters) - Chicago corn futures rose for a third consecutive session on Friday on short-covering, although concerns over weak U.S. exports limited gains.
Wheat was little changed after falling 1.7 percent on Thursday while soybeans rose, ending a three-session losing streak.
The Chicago Board of Trade December corn gained 0.3 percent to $3.56-3/4 a bushel by 0359 GMT, wheat was flat at $4.09-1/4 a bushel and soybeans up 0.3 percent to $9.88-1/4 a bushel.
Commodity funds hold massive net short positions in both corn and wheat, leaving those markets vulnerable to short-covering rallies.
But prices are being held back by lower-than-expected U.S. weekly export sales.
The U.S. Department of Agriculture reported export sales of U.S. corn in the latest week at 599,200 tonnes, below a range of trade expectations for 700,000 to 1,100,000 tonnes.
Weekly wheat sales totalled 187,400 tonnes (old and new crop years combined), also below expectations.
For soybeans, weekly U.S. export sales totalled 942,900 tonnes, in line with trade expectations.
CBOT soybean futures are being pressured by beneficial rains in Argentina’s crop belt and the U.S. Environmental Protection Agency’s biofuel mandates.
The EPA set a 2019 target for soy-based biodiesel at 2.1 billion gallons, unchanged from 2018, a factor that disappointed those hoping for an increase.
The wheat market is burdened by record world supplies.
“Wheat markets will tighten slightly as we move into 2018, but large carry-over stocks and a balanced market after the 2018 harvest in the northern hemisphere will prevent prices from averaging above U.S. 465 cents bushel,” according to BMI Research, a unit of Fitch Group.
Still, the wheat crop in Australia, the world’s fourth largest exporter, is being threatened by a monster storm after drought reduced yields earlier in the year.
And Russia’s winter grain sowings are in a worse condition than a year ago, but snow and rains may help in December, the head of the weather forecaster Hydrometcentre said on Thursday.
Russia, one of the world’s largest wheat exporters, harvested a record grain crop this year mostly due to favourable weather in spring and early summer.
Canadian farmers harvested the biggest canola crop on record, slightly larger than was expected in September, a Reuters survey of 15 traders and analysts showed ahead of a key government report. (Reporting by Naveen Thukral; Editing by Vyas Mohan)