Objective  The suitable saline-alkali resistant agents were screened for rice production in saline-alkali soil.

  Methods  The early rice variety Lingliangyou 942 and late rice variety Yliangyou 911 were taken as materials, the effects of several saline-alkali resistant agents (T₁ micro-nano silicon, T₂ mineral source fulvic acid potassium, T₃ saline-alkali, T₄ Soilfix IR + mineral source fulvic acid potassium) on osmotic adjustment substances, root activity and yield of rice under saline-alkali stress (CK₁ saline-alkali stress and CK₂ non-saline-alkali stress) were studied by pot culture method.

  Results  The results showed that the SPAD value, osmotic adjustment substance, root activity and yield of rice were affected by saline-alkali stress, and the effect caused by moderate stress was higher than that caused by mild stress. Application of saline-alkali resistant agents was beneficial to alleviate the effect of saline-alkali stress, and the effect was more significant when saline-alkali stress was serious. Under moderate saline-alkali stress, compared with CK₁, SPAD value, root activity, and yield of leaves were significantly increased when T₁, T₂, T₃, and T₄ were applied, while free proline content and soluble sugar content of leaves decreased significantly. Compared with CK₂, the yield of CK₁ decreased by 40.8%, and the yield of Yliangyou 911 was significantly reduced under saline-alkali stress by applying salt-alkali resistant agents. The yields of T₁, T₄, T₃, and T₂ were higher than those of CK₁ by 53.9%, 31.1%, 21.1%, and 16.3%, respectively. T₁ and T₄ had the best comprehensive performance among different treatments.

  Conclusion  The application of T₁ and T₄ is an effective measure to increase rice yield and income in saline-alkali soil.