At 12.1 billion bushels, the USDA's September Crop Production report reduces production 216 million bushels on lower than expected yields.

The forecast yield of 152.3 bushels per acre is down 2.7 bushels from last month.

Soybean production is forecast at 2.93 billion bushels, down 1pc from the August forecast but up 13pc from last year.

After the release, the Alliance for Agricultural Growth and Competitiveness again called for the penalty-free, early opt-out release of Conservation Reserve Program acres.

Analysts expect at least 5 million more acres need to be brought into production in 2009 to meet growing demand for grains and soybeans.