Oct 16 (Reuters) -Basis bids for soybeans hauled by barge to the U.S. Gulf Coast and loaded for overseas shipment firmed on Wednesday on strong demand and tight supplies of top quality beans in the export pipeline, traders said.

* A recent futures price slump has discouraged Midwest farmers from selling more newly harvested soybeans to barge-loading river elevators. As a result, some exporters did not have enough high-quality Midwest beans to blend with damaged supplies from the Delta harvest, traders said.

* Solid demand from top soy importer China for shipments through the end of the year also underpinned values, traders said.

* The U.S. Department of Agriculture (USDA) on Wednesday confirmed private sales of 175,000 metric tons of U.S. soybeans to undisclosed buyers.

* CIF October soybean barges were bid 2 cents higher at about 106 cents over CBOT November SX24 soybean futures.

* FOB offers for November soybean shipments rose 7 cents to 135 cents over futures. December through February offers also gained.

* Basis bids for corn barges at the Gulf were steady to mostly higher on good export sales and slow farmer selling which has tightened supplies in the river market.

* The USDA on Wednesday said Mexican importers bought more than 1.6 million tons of U.S. corn, including about 1 million tons for shipment in the current season. The sale, traders said, was part of a large annual purchase of rail-delivered grain by corn processors.

* The USDA also confirmed 332,000 tons in corn sales to undisclosed buyers.

* CIF corn barges loaded in October were bid 3 cents higher at 81 cents over CBOT December CZ24 futures.

* FOB Gulf offers for November and December corn shipments held at about 115 cents over futures.

Reporting by Karl Plume; Editing by Shreya Biswas

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