(Updates U.S. market activity to close)
By Michael Hirtzer
CHICAGO, Sept 27 (Reuters) - U.S. grain and oilseed futures were higher on Tuesday, with soybeans rebounding from an earlier five-month low on support from investor short-covering ahead of a U.S. Department of Agriculture quarterly stocks report due on Friday.
Rainfall delayed the U.S. corn and soybean harvests, while heavy precipitation could curb wheat output in Australia and reduce grain quality in Canada.
However, global supplies of cereal grains and edible oilseeds were abundant, likely limiting the upside potential in prices, traders and analysts said.
Chicago Board of Trade wheat futures posted the largest gains, with December wheat jumping 2 percent, or 8 cents, to $4.04 per bushel, while MGEX December spring wheat climbed 8-1/4 cents to $5.02-3/4 per bushel.
"Wheat overall is up on Australian wheat concerns and spring wheat is up on quality concerns after recent rain events in Canada," said Adam Knosalla, broker at Frontier Futures.
More showers were predicted later this week in eastern Australia after near-record rain earlier in September, and the excess moisture would likely add to crop loss in the part of country that typically produces high-protein wheat.
U.S. corn and soybean harvests were advancing slightly slower than average, USDA data showed late on Monday, prompting some investors to take profits on bearish bets.
CBOT November soybeans finished up 7-1/4 cents to $9.52-1/2 per bushel, rising sharply from their session low of $9.34 last reached in April. CBOT December corn was 2-3/4 cents higher at $3.31-3/4 per bushel, recovering from a roughly two-week low.
Top global soybean importer China likely bought soybeans near their session lows, ED&F Man Capital Markets analyst Charlie Sernatinger said in a note to clients. USDA earlier on Tuesday said China bought 120,000 tonnes of U.S. soybeans within the past 24 hours.
"Under the lows, the market ran head-on into big - and I mean big - Chinese pricing," Sernatinger said of soybeans.
Analysts polled by Reuters expected USDA on Friday to report U.S. stockpiles of wheat, corn and soybeans as of Sept. 1 above levels at the same time in 2015.
Rich Feltes, vice president for research at R.J. O'Brien, said early yield results for U.S. soybeans have been impressive.
"On a national basis we are seeing ... very few (anecdotal harvest) yields that are below USDA's number, at 50-plus (bushels per acre)," Feltes said. (Additional reporting by Julie Ingwersen in Chicago, Gus Trompiz in Paris and Naveen Thukral in Singapore; Editing by Richard Chang and Meredith Mazzilli)