Senator Lugar has noted that many countries with food shortages prohibit the importation of genetically modified grain. He's right about that, but that isn't the entire reason for the current shortages.
Americans have been eating genetically modifed food for years now. You probably had some for breakfast without knowing it since companies are not required to label products that contain GM grains. Genes do not make a plant toxic. Toxins make a plant toxic. Even though we've been eating this stuff for a while, Africans and Europeans still don't trust it.
The other cause of food shortages is the use of grains in ethanol production, something that Lugar wants the government to support through subsidies. Corn based ethanol is a waste of grain and money. It has not made a dent in gas prices. If we have more grain than we need for food and livestock feed, we should be exporting it. Food is a more basic need than oil, we could leverage our food and medicine exports when dealing with countries that are dependent on them.
But if domestic grain production surpasses domestic needs, and no other country wants to buy it off of us, then many farmers should consider other lines of work.