1. College of Landscape Architecture and Forestry, Qingdao Agricultural University, Qingdao, Shandong 266109, China
2. State Key Laboratory of Vegetable Biobreeding, Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing 100081, China
3. Key Laboratory of Biology and Genetic Improvement of Horticultural Crops, Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Ministry of Agriculture and Rural Affairs, Beijing 100081, China
4. College of Engineering, China Agricultural University, Beijing 100083, China
5. College of Horticulture, China Agricultural University, Beijing 100193, China