Abstract: 【Objective】 To clarify the effects of different amendments on soil salinization indexes,sunflower agronomic characteristics and yield in Hetao Irrigation Area,so as to provide a reference for the improvement of saline-alkali soil in this area.【Methods】 Randomized block test was used,4 treatments with no amendment（S1）,900 kg/hm² organic amendment（S2）,4 500 kg/hm² desulfurized gypsum（S3）,900 kg/hm² organic amendment + 4 500 kg/hm² desulfurized gypsum（S4）,comparative analysis of soil salinization indexes and sunflower agronomic characteristics and yield under different amendments.【Results】 The application of amendments reduced the total salt content and pH value of the soil compared with no amendments. The S4 treatment was significantly lower than the S1 treatment（P<0.05）,which decreased by 1.15 g/kg and 0.32,respectively. The application of amendments increased plant height,stem thickness,and disk diameter,and the S4 treatment was significantly higher than the S1 treatment（P<0.05）. The yield,grain weight per tray,and 100-seed weight of S4 treatment were significantly higher than those of S1 treatment（P<0.05）,increasing by 13.92%,21.15 g and 1.48 g respectively. There was no significant difference between S2 and S3 treatments（P>0.05）.【Conclusion】 900 kg/hm² organic amendment + 4 500 kg/hm² desulfurized gypsum had obvious effects on reducing the total salt content and pH value of the soil,promoting sunflower growth and increasing yield. It was a suitable amendment in saline-alkali soil of Hetao Irrigation Area.

Key words: Saline-alkali soil, Amendment, Desulfurized gypsum, Sunflower, Agronomic characteristics, Yield