1. State Key Laboratories for Agrobiotechnology/College of Biological Sciences, China Agricultural University, Beijing 100193, PR China
2. Departamento de Microbiología, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, 11340 México D. F., Mexico
3. Agricultural Culture Collection of China, Institute of Agricultural Resource and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing 10081, PR China
4. Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, PR China