Effects of Selenium and Mycorrhiza on Grain Yield and Some Biochemical and Physiological Traits of Rye (Secale cereale L.) under Salinity Stress

Abstract This study investigated the effects of selenium (Se) and mycorrhiza on the yield and some biochemical and physiological traits of rye under salinity stress. The experiment was conducted in a factorial arrangement using a randomized complete block design with three replications, under greenhouse conditions in 2024. The treatments included three salinity levels (without salinity as control, salinity of 65, and 130 mM NaCl), two mycorrhizal levels (with and without Glomus mosseae), and foliar application of selenium (foliar application with water as control, 1.5, 3, and 4.5 mg/L of Se). The results indicated that salinity stress significantly decreased relative water content (RWC), anthocyanin content, DPPH radical scavenging activity, and grain yield, whereas proline content increased under salinity conditions. However, the combined application of mycorrhiza and Se substantially mitigated the adverse effects of salinity. At the highest salinity level, the application of mycorrhiza and 4.5 mg/L of Se led to an increase of 41.2, 91.6, 74.9, 37.6, 64.6, and 75.3% in RWC, peroxidase activity, superoxide dismutase activity, anthocyanin content, DPPH radical scavenging activity (DPPH), and grain yield, respectively, compared to the control (without mycorrhiza and Se) at the same salinity level. Furthermore, arbuscular mycorrhizal fungi and selenium improved plant ionic balance and enhanced salinity tolerance by reducing sodium accumulation and increasing potassium uptake in both roots and leaves. Overall, it was concluded that the application of mycorrhizal and Se can be considered an effective strategy to improve rye yield under salinity conditions.