Comparative Effects of Hydropriming and NaHS-Priming on Salinity Tolerance in Brassica napus L. Seedlings.

Salinity stress significantly restricts crop productivity by impairing germination and early seedling growth through osmotic, ionic, and oxidative damage. The present study evaluated whether sodium hydrosulfide (NaHS) priming confers greater protection than hydropriming in B. napus (Brassica napus L). Seeds were primed with water, 0.1 mM NaHS, or 10 mM NaHS and then germinated under saline conditions. Parameters measured included germination rate, root length, endogenous hydrogen sulfide (H2S) content, antioxidant capacity, oxidative stress markers, and membrane integrity. Salinity reduced germination to 30% and root length to 1.6 mm in unprimed seeds. Both 0.1 mM and 10 mM NaHS priming produced more substantial improvements in these parameters compared to hydropriming. The most pronounced effect was observed with 10 mM NaHS, which after 48 h increased germination to 100% and root length to 30 mm. Furthermore, 10 mM NaHS priming most effectively elevated endogenous H2S levels, enhanced antioxidant capacity (60.43 µM TE/g FW at 24 h), reduced hydrogen peroxide (H2O2) (2.04 nmol g-1 FW at 48 h) and thiobarbituric acid reactive substances (TBARS) (0.008 mmol g-1 FW at 48 h), and preserved membrane integrity by limiting Evans staining and electrolyte leakage. In summary, NaHS priming provided substantially greater mitigation of salinity-induced damage than hydropriming in B. napus.