1. State Key Laboratory of Soil Erosion and Dry Land Farming on the Loess Plateau, Institute of Soil and Water ConservationNorthwest A&F University Yangling Shaanxi PR China
2. State Key Laboratory of Crop Stress Biology for Arid Areas, Shaanxi Key Laboratory of Agricultural and Environmental Microbiology, College of Life ScienceNorthwest A&F University Yangling Shaanxi PR China
3. Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of BotanyChinese Academy of Sciences Kunming Yunnan PR China