Bloomberg: Ethanol rises to three year high as heat threatens corn crop

http://www.bloomberg.com/news/2011-07-15/ethanol-rises-to-three-year-high-as-heat-threatens-corn-crop.html

QUOTE: 'The grain-based additive gained as temperatures reaching 100 degrees Fahrenheit (37.8 Celsius) move across the corn-rich U.S. Midwest. Ethanol is made mostly from corn in the U.S., with one bushel making at least 2.75 gallons.'

I'm curious what, if any, impact the heat wave will have on food production, such as corn not used for ethanol but for consumption?  This could be yet one more threat to the food supply, along with all the others we've seen over the past year or two.