1. Huazhong Agricultural University Microelement Research Center 430070 Wuhan China
2. Hubei Provincial Engineering Laboratory for New-Type Fertilizer 430070 Wuhan China
3. Jianshi Soil and Fertilizer Station of Hubei Province 445300 Jianshi Hubei China
4. Institute of Oil Crops, Chinese Academy of Agricultural Sciences 430062 Wuhan China