Evaluation of Salinity Tolerance and Alleviation Potential in Sweet Sorghum (Sorghum bicolor L.) and Switchgrass (Panicum virgatum L.)

This study assesses the phytoremediation potential and biomass production of sweet sorghum (Sorghum bicolor L.) and switchgrass (Panicum virgatum L.) under saline field conditions in 2024 and 2025. Salinity was defined based on electrical conductivity (EC), and phytoremediation performance was evaluated in this study. Sweet sorghum consistently produced high biomass (56.700–78.600 kg/ha), yet saline irrigation decreased its yield by 6% in 2024 and 11% in 2025, alongside a 19% reduction in plant height in 2025. Conversely, saline irrigation promoted switchgrass growth, increasing biomass yield from 2548 to 3643 kg ha−1 (43%) in 2024 and from 4503 to 5812 kg ha−1 (29%) in 2025. Plant height also increased by up to 35% in 2025 under saline conditions. In this study, when the Na+ (me/L) results at 10 cm of irrigated soil under saline conditions were examined, sorghum and switchgrass plants produced statistically significant differences in their saline-irrigated plots compared to their plots irrigated with non-saline water. In contrast, no significant differences were observed between sorghum and switchgrass in terms of soil Na removal under either saline or non-saline irrigation conditions. Therefore, both plants have a similar sodium reduction capacity.