The International Grains Council lowered the bar on estimates for world corn stocks, citing higher estimates for consumption, but the downgrade failed to prevent corn's rally losing traction after eight days of gains.

The IGC lowered by 3m tonnes to 113m tonnes, a nine-year low, its forecast for world corn inventories at the close of 2012-13.

"The market is particularly tight," the intergovernmental group said, flagging that inventories in the four main exporting countries were now set to end the season at 25m tonnes, 3m tonnes below the previous forecast, and down 46% on average levels.

Stocks in major exporters – Argentina, Brazil, Ukraine and the US – are viewed as particularly significant as they are available to for trade, unlike the inventories in countries such as China, the second-ranked producer, which rarely sells supplies abroad.

Below USDA

The IGC lifted by 15m tonnes to 845m tonnes, citing upgrades to official estimates for the Chinese and US crops, and "brighter prospects for Argentina".

However, the revision was more than offset by a hike to 865m tonnes in the forecast for consumption over 2012-13, with the council flagging the US Department of Agriculture's higher estimate for domestic feed use, as revealed in a slew of data last Friday.The IGC's estimate for world corn stocks at the close of 2012-13, of 113m tonnes, was lower than the USDA's downgraded 116m-tonne estimate on Friday, which has helped prolong a rally in corn futures to eight successive sessions.

And, it represents less than 48 days' of consumption – the thinnest level of cover for 39 years.

'Getting stale'

However, Chicago corn futures looked set to break their winning streak despite the IGC report, and separate USDA data showing US weekly export sales of the grain at 393,341 tonnes – up from 12,622 the week before and a figure beaten only once before this season.

The sales, which came during the week that corn futures set a six-month low of $6.78 a bushel, were largely to China, Japan and Mexico.

Nonetheless, corn for March stood 0.4% lower at $7.28 a bushel, for March delivery, in midday deals, with traders citing rally fatigue.

The bullish news from the USDA's data last week "is getting stale", Richard Feltes at RJ O'Brien said.

US Commodities said that corn for delivery in 2012-13 was "overbought 1.2 times", terming the market as "mature" and "awaiting a catalyst of the next technical move".