[1] Univ Wisconsin, USDA, Vegetable Crops Res, Agr Res Serv,Dept Hort, Madison, WI 53706 USA
[2] ARS, USDA, Forage & Range Res Lab, Logan, UT 84322 USA
[3] ARS, USDA, US Sugarcane Field Stn, Canal Point, FL 33438 USA
[4] N Carolina State Univ, Dept Hort Sci, Raleigh, NC 27695 USA