1. School of Agriculture, Yunnan University, Kunming 650091, China
2. College of Agriculture, Nanjing Agricultural University, Nanjing 210095, China
3. Department of Crop, Soil, and Environmental Sciences, University of Arkansas, Fayetteville, AR 72701, USA
4. USDA-ARS Beltsville Agricultural Research Center, Beltsville, MD 20705, USA
5. Agricultural Research Station, College of Agriculture, Virginia State University, Petersburg, VA 23806, USA