1. Institute of Vegetable Science, Zhejiang University, Hangzhou, 310029 China
2. College of Horticulture and Gardening,Yangtze University, Jingzhou, 434025 China
3. Beijing Agro-biotechnology Center, Beijng, 100089 China
4. Institute of Soil Science, Chinese Academy of Sciences, Nanjng 210008 China