Physiological Impacts of Seed Ageing on Germination and Seedling Vigour in Brassica Species

Seed ageing significantly affects the physiological quality, germination capacity, and seedling vigour of Brassica species, which critical challenges for global agriculture. This study examines the effects of ageing on germination and early growth in six Brassica varieties under controlled and field conditions. Ageing processes, including increased accumulation of reactive oxygen, lipid peroxidation, and protein oxidation, impair cellular membrane integrity, as reflected by increased electrical conductivity (EC) values in aged seeds. Germination rates declined significantly, with aged seeds showing a 72.5% germination rate for Potsangbam Yella compared to 95.5% in fresh TS-36 seeds. Similarly, the seedling vigor index (SVI) for aged PM-28 seeds decreased to 66.20, compared to 94.81 in fresh TS-36 seeds. TS-36 exhibited strong tolerance to ageing, whereas Potsangbam Yella showed the greatest decline in seed quality. These results enhance the importance of optimized storage practices and highlight non-destructive EC testing as a practical tool for seed viability evaluation. The findings have significant implications for advancing seed storage protocols, enhancing breeding strategies, and promoting agricultural sustainability.