Crops weakened in listless trade on Tuesday, as investors prepared for key data it is hoped may put a bit of vim back into the market.

Currencies provided somewhat of a more interesting backdrop, with the euro weakening after Greece's prime minister, George Papandreou, warned of the lingering risks from Greece's economic crisis, and urged a clampdown on credit market speculators.

Sterling fell back below $1.50 after Moody's, the ratings agency, said that the UK faces a difficult choice in deciding how, and when, to trim support for banks. It even lost ground against the euro, which settled in well above £0.90.

The dollar's strengthening cut the competitiveness of US exports such as commodities, so acting to weaken Chicago prices.

'Increased farmer selling'

And there were few investors willing to push back far ahead of the US Department of Agriculture's global crop report on Wednesday, a key event in the food commodities calendar in any event, but particularly so this time for corn watchers as it will come up with fresh estimates for the US 2009-10 harvest.

The revision has been prompted by long delays to the harvest, which meant many crops overwintering in the field.

That said, the report may have to go some to get some analysts into a bullish frame of mind.

"We are to see increased farmer selling in the days and weeks after Wednesday regardless of price action," eHedger said.

"Whether we see a bullish, bearish, or neutral corn figure bushels need to be moved as temperatures heat up and bin quality becomes a larger concern."

Corn vs soybeans

The one ongoing factor which is managing to make itself felt over the hubbub of USDA data is the weather.

Some forecasters are predicting a wet spring which, added to significant amounts of snowmelt expected, could hinder spring plantings.

One dynamic here is corn vs soybeans. As the former is planted earlier, it is viewed as vulnerable, if conditions prove wet, to substitution with soybeans, which are somewhat more flexible with sowings. So wet forecasts have been tending to send corn higher and soybeans lower.

Minneapolis vs Chicago

However, Minneapolis-traded wheat, which is planted in the spring, versus the winter-sown Chicago and Kansas grains is another.

"Fears of reductions to spring wheat acres due to delayed planting on flood fears, as well speculation that a shift toward higher protein/lower yielding wheat, should help Minneapolis extend the gains that it currently holds versus the other classes," Dave Lehl at Benson Quinn Commodities said.

"The spread between Kansas City and Chicago [contracts] doesn't seem to have too much movement to it."

Chicago wheat for March was 2.75 cents lower at $4.81 ¾ a bushel at 08:00 GMT, with the May lot down 2.25 cents at $4.92 ¾ a bushel.

Corn was down 1.25 cents at $3.63 ¼ a bushel for March and by 0.75 cents to $3.74 ¼ a bushel for May.

Soybeans for March managed to get into positive ground, adding 0.5 cents to $9.41 a bushel, while the May lot slipped 0.75 cents to $9.47 ¼ a bushel.

Buy on rumour... 

Kuala Lumpur palm oil, for once, wasn't in much better form, standing unchanged at 2,709 ringgit a tonne despite some bullish statements from a conference organised by Bursa Malaysia.

Much-watched analyst Dorab Mistry, for instance, said that palm oil may approach 3,200 ringgit after July as the hangover from El Nino hits plantation production.

Still, as the old saying goes, buy on rumour, sell on fact.

Indeed, palm oil, which has gained some 11% since late January, for the first time in a week failed so far to set an intraday high above that of the previous day.