Wheat prices are falling on expectations that wet weather in the Plains region will help farmers grow more grain this year.
The price of wheat for May delivery fell 22.25 cents, or 3.2 percent, to $6.8375 a bushel, dropping below $7 a bushel for the first time since June 22.
This year's weather patterns in the Plains region suggest that wheat farmers will experience a more normal growing season after last year's drought.
Expectations that India will boost exports also weighed on prices.
Meanwhile, prices for corn fell and soybean prices were unchanged.
In energy trading, the price of crude fell 39 cents to $90.34 a barrel.
Metal prices were mixed: Silver and palladium rose, while copper and platinum fell. Gold was unchanged.