1. Graduate student and professor, respectively, Department of Food Science and Human Nutrition and Center for Crops Utilization Research, Iowa State University.
2. Research geneticist, USDA-ARS, Corn Insects and Crops Genetics Research Unit, Department of Agronomy, Iowa State University.
3. Technical manager, MBS Incorporated, Story City, IA 50248.
4. Corresponding author. Phone: 515/294-9688. Fax: 515/294-8181. E-mail: pjwhite@iastate.edu