Record figures for maize production released by the United States caused a fall in grain prices on the commodity markets last week.
The latest US Department of Agriculture survey predicted a 6.3m tonne increase in world maize production compared to its December figures.
This latest increase brings the expected world maize harvest to 796.5m tonnes and US production to 334m tonnes.
Commodity traders subsequently sold considerable amounts of grain stocks, causing prices on the major markets to fall.
Maize prices fell by 7pc and wheat fell by 6pc on the US markets.
Closer to home, wheat prices on the French MATIFFE market fell by 3pc and feed wheat on the London LIFFE fell by 1.5pc.
In monetary terms, French milling wheat fell by €4/t, from €134-136/t to €130-134/t.
Spot prices for Irish barley fell by €2-5/t, from €120/t to €115-118/t.
However, spot prices recovered later in the week by €1/t.
Some analysts believe the fall in prices could be a slight over-reaction by traders to the figures released by the USA.
They argue that the latest survey was conducted when some of the major maize- producing states had not yet harvested their crops.
Illinois, Michigan, Minnesota, North and South Dakota, and Wisconsin, accounting for 10pc of national harvest, had not been harvested when the survey was carried out.
Meanwhile, estimates of world wheat production have also been increased by 2.3m tonnes since last month's estimate, bringing the total expected harvest to 676m tonnes.
The majority of this increase is due to a 2.2m tonne rise in the expected Russian harvest since last month.
However, the 676m tonne forecast remains 6.6m tonnes below the previous year's harvest.
Estimates of the world carry-over of wheat stocks have risen by 4.4m tonnes in the past month, due to the higher Russian figures and expected lower consumption in Europe.
Early indications for the 2010/2011 harvest show that US sowings are down by 14pc.
This figure consists of a 12pc fall in hard red wheat sowings and a 29pc fall in soft red wheat sowings.