Abstract:The seeds of tartary buckwheat variety“Heifeng No.1” were used as experimental material in pot during 2012,in order to study the effect of soaked seed with four different chemical regulators on the growth of tartary buckwheat under different water conditions and to find the best chemical regulators to improve the drought resistance of tartary buckwheat,the four chemical regulators are:ZnSO4,MnSO4,SA and Pro.The main result showed that:(1)At normal irrigation,soaked seeds with the chemical regulators increased the leaf area,plant height,total root length,root volume,seedling index,leaf relative water content,proline content,soluble sugar content,root activity,SOD and POD activities and photosynthesis,while the treatment of ZnSO4 is the most effective to the growth of tartary buckwheat,SA is the latter,both of them are significant difference from the CK at 0.01 level.Finally,the treatment of ZnSO4 and SA can increase the number of spikes by 31.8% and 21.0%,grains per plant can be gained by 38.0% and 28.9%,and 100-seed weight can be added by 8.9% and 4.2%,respectively.However,the relative conductivity and MDA content of tartary buckwheat are dropped obviously.(2)Compared water stress and normal irrigation,the indexes of the leaf area,stem thickness,total root length,root volume,root weight,leaf relative water content,proline content,chlorophyll content,soluble sugar content,root activity,SOD and POD activities and photosynthesis are reduced,while relative conductivity and MDA content are increased by soaking with chemical regulators.The extents differed in the treatment of different chemical regulators,and soaked with H2O is changed most in all indexes.(3)At water stress,soaked with ZnSO4 and SA can significantly improve SOD and POD activities,photosynthesis,leaf area,total root length,chlorophyll content and root activity compared with CK.They can increase leaf relative water content by 79.9% and 70.9%,proline content by 32.2% and 36.6%,and soluble sugar content by 66.0% and 43.9%,respectively.The number of spikes,grains per plant and 100-seed weight can gained by 38.6% and 36.2%,40.4% and 39.0%,10.7% and 6.9%,separately.The research indicated that using chemical regulators can remarkable raise the photosynthetic physiological characteristics and drought resistance of tartary buckwheat under normal irrigation and water stress.The treatment of ZnSO4 and SA are the best.