Silicon Compounds and Potassium Sulfate Improve Salinity Tolerance of Potato Plants through Instigating the Defense Mechanisms, Cell Membrane Stability, and Accumulation of Osmolytes

Potato (Solanum tuberosum L.) as a strategic crop is moderately susceptible to salinity. Therefore, it is essential to recognize the defense mechanisms upon which potato plants respond to salinity stress and adopt strategies to enhance their salinity tolerance. An open field experiment was conducted at different saline irrigation water (0.5, 5, 8, and 12 dS.m(-1)) to investigate the physicochemical traits and tuber yield of potato plants under antistress compounds application, including K2SO4, NaSiO3 nanoparticles (NaSiO3-NPs), and SiO2. The results showed that gas exchange variables were suppressed by salinity stress, while they were alleviated by foliar application of K2SO4. The lowest leaf malondialdehyde content was observed at 5, and 12 dS.m(-1) in SiO2 and NaSiO3-NPs-treated plants showed 56% and 43% decreases, respectively, over control. The application of silicon under saline conditions increased leaf soluble carbohydrates and proline content compared with the control. While salinity increased the Na+/K+ ratio, the application of silicon reduced Na+/K+ more than twice compared with the control. The antioxidant enzyme activities were induced the most by NaSiO3-NPs. It seems that the use of antistress compounds, especially nanoparticles, would be a practical approach to alleviate the detrimental effects of salinity stress on potato plants.

Automated summary

Potato plants, moderately susceptible to salinity, show improved gas exchange and decreased malondialdehyde content when treated with K2SO4, SiO2, and NaSiO3-NPs under saline conditions. Silicon application increases soluble carbohydrates and proline content, while reducing Na+/K+ ratio compared to the control. NaSiO3-NPs induce the highest antioxidant enzyme activities, suggesting their potential use to alleviate salinity stress effects on potato plants.