1. Mountain Area Research Inst., Hebei Agricultural Univ. Baoding PR China
2. State Key Laboratory of North China Crop Improvement and Regulation, Hebei Agricultural Univ. Hebei Baoding PR China
3. Soil Science&Plant Nutrition, UWA School of Agriculture and Environment, The Univ. of Western Australia Perth Australia
4. Inst. for Adriatic Crops and Karst Reclamation Split Croatia
5. Inst. of Environment and Sustainable Development in Agriculture, Chinese Academy of Agricultural Sciences Beijing PR China