1. Dep. of Crop Science; N.C. State Univ.; Raleigh NC 27695-7629
2. USDA-ARS National Program Staff; 5601 Sunnyside Ave., GWCC-BLTSVL Beltsville MD 20705
3. USDA-ARS Soybean and Biological Nitrogen Fixation Group; N.C. State University; Raleigh NC 27695-7620