Field practice model of undergraduate for pratacultural scienceA case of Gansu Agricultural University

• Wen-xia CAO, 
• De-gang ZHANG, 
• Xiao-peng PU, 
• Chang-lin XU, 
• Tuo YAO, 
• Gui-xin HU, 
• Zhuo-shan CAI, 
• Ya-juan LI