Affiliation: | 1. Department of Grassland Science, Animal Science and Technology College, Sichuan Agricultural University, Ya'an, Sichuan, China;2. Agronomy Department, University of Florida, Gainesville, FL, USA;3. Department of Horticulture, Virginia Tech, Blacksburg, VA, USA;4. Department of Crop, Soil, and Environmental Sciences, University of Arkansas, Fayetteville, AR, USA |