State Key Lab of Crop Genetics and Germplasm Enhancement, College ofAgriculture, Nanjing Agricultural University, Nanjing 210095, China;
Department of Agrobiodiversity, Institute of Crop Science, University of Kassel, 34109 Kassel, Germany;
and Leibniz Institute of Plant Genetics and Crop Plant Research (IPK), Corrensstr. 3, 06466 Gatersleben, Germany;