USDA-ARS,Crop Science Research Laboratory,P.0.Box 5367,Mississippi State,Mississippi 39762,USA;
USDA-ARS,Crop Science Research Laboratory,P.0.Box 5367,Mississippi State,Mississippi 39762,USA;
USDA-ARS,Crop Science Research Laboratory,P.0.Box 5367,Mississippi State,Mississippi 39762,USA;
USDA-ARS,Crop Science Research Laboratory,P.0.Box 5367,Mississippi State,Mississippi 39762,USA;
Dept.Soil & Crop Sciences,TAMU,College Station,Texas 7843-2474,USA;