[1] N Carolina State Univ, Dept Plant Pathol, Box 7616, Raleigh, NC 27695 USA
[2] N Carolina State Univ, Dept Hort, Raleigh, NC 27695 USA
[3] Univ Wisconsin, Dept Agron, 1575 Linden Dr, Madison, WI 53706 USA
[4] Univ Delaware, Dept Plant & Soil Sci, Newark, DE 19716 USA
[5] USDA ARS, Plant Sci Res Unit, Raleigh, NC 27695 USA