1. The State Key Lab. of Crop Stress Biology for Arid Areas, College of Agronomy Northwest A&F Univ. Yangling Shaanxi 712100 PR China
2. Faculty of Agronomy S. Seifullin Kazakh AgroTechnical Univ. Astana Kazakhstan
3. Institute of Water Saving Agriculture in Arid Regions of China Yangling Shaanxi 712100 PR China