GRAINS-Soybeans, corn fall on US harvest pressure

By Naveen Thukral and Sybille de La Hamaide

SINGAPORE/PARIS, Sept 29 (Reuters) - Chicago soybean and corn futures slid on Monday, starting the week on a bearish note due to seasonal harvest pressure in the United States with soybeans facing additional weakness from China's absence from the market.

Wheat edged higher.

"U.S. soybean inventories are going to increase in the coming weeks, as there is lower demand for U.S. soybeans and we have supplies coming from the ongoing harvest," said an oilseed trader in Singapore.

The most-active soybean contract on the Chicago Board of Trade Sv1 lost 0.35% to $10.10-1/4 a bushel by 1013 GMT, corn was down 0.5% to $4.20 a bushel and wheat Wv1 rose 0.1% to $5.20-1/4 a bushel.

The advancing U.S. soybean and corn harvests are putting supply pressure on prices, though doubts over the size of corn yields had lent some support to that market in recent sessions.

The U.S. Department of Agriculture is scheduled to issue a weekly update on harvesting progress on Monday. On Tuesday, the agency is set to issue quarterly data on U.S. grain stocks.

U.S. soybean exporters are missing out on business to China amid a trade war between the two nations, with rival suppliers from Latin America taking their share.

After Buenos Aires briefly suspended grain export taxes last week, around 40 Argentine soybean cargoes were registered for export in November and December, mostly headed to China, two traders told Reuters. These purchases are directly eating into the prime U.S. marketing season.

Large speculators increased their net short position in CBOT corn futures in the week to Sept. 23, regulatory data released on Friday showed.

The Commodity Futures Trading Commission's weekly commitments of traders report also showed that noncommercial traders, a category that includes hedge funds, increased their net short position in CBOT wheat and soybeans.