1. College of Forestry, Nanjing Forestry University, Nanjing, Jiangsu 210037, China; Institute of Botany, Jiangsu Province and Chinese Academy of Sciences (Nanjing Botanical Garden Mem. Sun Yat-Sen), Nanjing, Jiangsu 210014, China; and Jiangsu Qinghao Landscape Horticulture Co., Ltd., Nanjing, Jiangsu 211225, China
2. College of Forestry, Nanjing Forestry University, Nanjing, Jiangsu 210037, China
3. Institute of Botany, Jiangsu Province and Chinese Academy of Sciences (Nanjing Botanical Garden Mem. Sun Yat-Sen), Nanjing, Jiangsu 210014, China
4. Jiangsu Academy of Forestry, Nanjing, Jiangsu 211153, China
5. College of Forestry, Nanjing Forestry University, Nanjing, Jiangsu 210037, China; and Jiangsu Qinghao Landscape Horticulture Co., Ltd., Nanjing, Jiangsu 211225, China
6. Department of Horticulture, University of Georgia, Athens, GA 30602, USA