Potassium Silica Nanoparticles Enhanced Growth, Yield, and Stress Tolerance in Canola (Brassica napus L.) Under Drought Conditions

This study explores the effects of potassium silica nanoparticles (PSNs) on the physiological traits, yield, and stress tolerance of canola under drought conditions during the 2023 and 2024 growing seasons. The goal is to assess temporal variations in PSN effectiveness and distinguish the individual contributions of potassium and silicon in mitigating drought stress. A randomized complete block design with three replications was used. Canola plants were subjected to non-stress (-0.03 MPa) and severe drought stress (-1.2 MPa) conditions, combined with PSN treatments at 0 ppm (control) and 200 ppm. Severe drought stress significantly reduced plant height (by 51.4 cm), dry weight (17.87 g), seed yield (1692.34 kg ha(-)(1)), seed oil percentage (41.19%), and oil yield (925 kg ha(-)(1)). PSN application significantly mitigated these reductions, improving plant height by up to 51.4 cm and seed yield to 3935.67 kg ha(-)(1) under non-stress conditions in 2023. Electrolyte leakage (EL) increased by 41.23% under drought stress, highlighting the extent of membrane damage caused by water deficit. PSN application reduced EL more effectively in 2023 than in 2024, indicating seasonal variations in its effectiveness. While PSN improved physiological traits and yield, its influence on antioxidant enzyme activity (peroxidase and catalase) was less pronounced compared to growth and yield traits. For instance, catalase activity increased under drought stress to 4.64 mu mol/min/protein in 2024, but PSN treatment had minimal effects on these enzyme levels. The study demonstrates that PSN application significantly alleviates drought stress effects on canola, with greater effectiveness observed in 2023 compared to 2024. These findings emphasize the role of PSNs in improving growth, yield, and drought tolerance by leveraging the complementary benefits of potassium and silicon. Temporal variations underscore the need to consider environmental factors when evaluating PSN efficacy.