Feb 1 (Reuters) -Basis bids for soybeans shipped by barge to the U.S. Gulf Coast were flat to lower on Wednesday on seasonally slowing export demand, while CIF corn basis bids were mostly steady to weak, traders said.

* Barge freight rates were mostly steady to lower as pressure from muted grain shipper demand was largely offset by reduced barge drafts at the Port of St. Louis and upriver, traders said. Low water prompted barge lines to restrict vessel drafts there, limiting the amount of grain that can be shipped in each barge.

* Export demand for U.S. Gulf soybeans has slowed as Brazil's harvest is ramping following some rain delays. Chinese importers have been booking March and April shipments from Brazil this week, traders said.

* Brazil's harvest delays triggered some light purchases by China of near-term shipments from the U.S. Pacific Northwest, which would reach the country sooner than Gulf shipments, traders said.

* The U.S. Department of Agriculture is due to release its latest weekly export sales report on Thursday morning.

* Bids for CIF soybean barges loaded in January were unquoted. February barge bids were 4 cents lower at 103 cents over Chicago Board of Trade (CBOT) March SH3 futures.

* FOB basis offers for February soybean shipments were steady at around 130 cents over March futures, while premiums for March shipments held at 120 cents over futures.

* Basis bids for CIF corn barges loaded in January were unquoted. February barges were bid a penny lower at 86 cents over CBOT March corn CH3 futures. March barges traded steady at 88 cents over futures before bids slipped to 87 cents over.

* FOB offers for February corn shipments held at around 90 cents over CBOT March futures, and March FOB offers were unchanged at 99 cents over futures.

Reporting by Karl Plume in Chicago

For displays of CIF basis, click on the codes in brackets: U.S. CIF Gulf soybeans GRYM U.S. CIF Gulf corn GRYN U.S. CIF Gulf SRW wheat GRYO U.S. CIF Gulf HRW wheat GRYP For displays of FOB basis, please click on the following codes in brackets: U.S. FOB Gulf corn GRZC U.S. FOB Gulf soybeans GRZD U.S. FOB Gulf SRW wheat GRZE U.S. FOB Gulf HRW wheat GRZF LINKS Corn prices page: cpurl://apps.cp./cms/?pageid=corn-cash-market
Wheat prices page: cpurl://apps.cp./cms/?pageid=wheat-cash-market
U.S. barge freight BG/US
U.S. export sales estimates USDA/EST U.S. grain export summary GRA/U Brazil soybean export prices SYBS Brazil corn export prices SYBX Argentina grain prices GRA/ARG Russia grain prices GRA/RU