By Gregory Meyer in New York, Jack Farchy in London and Javier Blas in Geneva

Published: November 9 2010 17:00

The spectre of inflation loomed over agricultural markets after the US slashed key crop forecasts and warned of shortfalls in grains.

The agriculture department on Tuesday cut estimates of US corn yields for a third successive month, forecast record soya bean exports to China and warned of the slimmest cotton stocks since 1925.

“The combined production shortfalls and dramatic potential stock drawdowns mean a much tighter supply picture than just a few months ago,” the agency said in a separate grains report.

Benchmark Chicago corn futures soared above $6 a bushel for the first time since August 2008, before ending lower. Soyabeans rose 4.3 per cent and New York cotton futures posted a record above $1.51 a pound. The price rises have revived fears of a repeat of the global food crisis

In Europe, milling wheat surpassed a peak reached after ­Russia banned grain exports in August in response to a devastating drought.

Abdolreza Abbassian, senior grains economist at the UN’s Food and Agriculture Organisation in Rome, said the report was “alarming”.

“It reiterates the tightening of the overall situation as we go into 2011, which means eventually even those basic food commodities that haven’t risen so much could be influenced,” he said. The FAO food price index is nearing the highs set in mid-2008.

The price gains will benefit farmers, who the USDA said would earn record amounts for corn this season. But consumers could face pain. Carlsberg, the brewer, on Tuesday warned of price increases as costs swelled for malt and barley. As northern hemisphere farmers contemplate next year’s crop plans, surging prices could generate a so-called battle for acreage among different crops.

Dan Basse, president of Ag Resource, a Chicago crop forecaster, said: “The world cannot afford to lose any more crop production going forward.”

Ricardo Leiman, chief executive of the trading house that is one of the top oilseed processors in China, cited “enormous demand” there because of “stronger economy, stronger habits, very strong feed milling margins and very strong prices domestically”.

The USDA said corn yields in the US, the world’s largest grower and exporter, would be 154.3 bushels per acre, down 1.5 bushels from an October forecast that was also a sharp downward revision. At 827m bushels, stocks left over from this year’s harvest would be the lowest in 15 years. Record US ethanol production has added to demand.

China’s surging demand looms large in cotton. The USDA took the rare step of lowering estimates of China’s 2010 supply cushion, citing “shortages in mill inventories”.

The USDA reduced its cotton demand estimate because of “supplies insufficient to meet demand”.

Mike Stevens, a veteran Louisiana cotton broker, said: “The report is the most bullish in our lifetime.”

Food price inflation rose at an annual rate of 8 per cent in China in September, according to USDA, whilst food inflation in the US has so far been tame, with the food index rising 1.4 per cent over the past 12 months.

Advisers scrambled to come to grips with the latest report, whose monthly appearance has caused big swings in agricultural markets.