CANBERRA, Nov 1 (Reuters) - Chicago wheat prices fell on Wednesday to match Tuesday's three-week low on strong supplies from Russia, lacklustre demand and less concern about small crops in southern hemisphere exporters.

Soybeans also slipped while corn edged higher.

Most-active wheat futures on the Chicago Board of Trade (CBOT) were down 0.2% at $5.55 a bushel by 0418 GMT, their fourth straight daily fall.

Prices rose in October due to fears that dry weather would further reduce yields in Argentina and Australia, but rain has fallen in both countries. Wheat is now nearing September's three-year low of $5.40.

"Current prices are low enough to encourage demand for U.S. wheat," said Ole Houe at Australian agricultural brokerage IKON Commodities, adding that this should support prices.

But upside is also limited for the time being because cheap supply from the Black Sea remains plentiful, he said.

"Longer term, wheat is well supported. Short term, there's plenty around."

Consultants Sovecon this week estimated Russia's October wheat exports at 4.4 million tons, down from 4.5 million tons a year ago. It said weak demand held FOB prices at $228-234 a ton, down $1 from the week before.

The success of Ukraine's new Black Sea export corridor has meanwhile led to a sharp increase in the number of rail wagons heading to ports in the Odesa region, a railways official said on Monday.

China is set to import record volumes of wheat this year following rain damage to its crop, trading sources said, but so far, it has bought from Europe and Australia rather than the United States.

Commodity funds were net sellers of CBOT wheat on Tuesday, traders said, and net buyers of corn and soybeans.

CBOT soybeans were down 0.2% at $13.07-1/2 a bushel on Wednesday while corn rose 0.1% to $4.79 a bushel.

Soybeans have recovered from a 22-month low of $12.51 last month as low production in Argentina boosted demand for U.S. beans and soymeal. Corn is near September's 33-month low of $4.68 amid plentiful supply.

Analysts polled by Reuters said the U.S. soybean crush likely increased in September to 5.249 million short tons, or 175.0 million bushels -- the largest September crush on record.

In Brazil, the world's top soybean exporter, farm group BrasilAgro has advanced soy planting in some parts of Mato Grosso state but has seen slower progress in others due to irregular rains, an executive said.

(Reporting by Peter Hobson; Editing by Rashmi Aich and Janane Venkatraman)