Effects of Hydro and Hormonal Seed Priming on Seed Germination of Milk Thistle under Saline Stress Condition

</style><p><span style="font-size: 10.0pt; font-family: 'Times New Roman',serif">Salinity is an abiotic stress which has harmful effects on germination of many plants. Therefore, high germination rate and vigorous early growth under salty soils is preferred. Seed priming is a way to increase salt tolerance of plants. An experiment was conducted to investigate the effect of seed priming on germination of milk thistle under salinity condition. The treatments were 4 levels of seed priming (no priming, distilled water as hydro priming and 0.5 and 1.0 mM salicylic acid) and 5 levels of salinity (0, 40 and 80 mM NaCl and 40 and 80 mM CaCl₂). The experiment arranged as a factorial in a completely randomized design (CRD) with three replications. Results showed that salinity decreased germination percentage and germination rate to about 16 and 32% in 80 mM CaCl₂ level compared to control, respectively. The highest mean germination time (5.7 day) were belonged to 80 mM CaCl₂. Radicle and plumule length significantly decreased by 80 mM NaCl and 40 and 80 mM CaCl₂. The lowest seedling weight and seed stamina observed in 80 mM CaCl₂. 0.5 mM salicylic acid improved all traits except mean germination time as compared to control.&nbsp; Salicylic acid (0.5 mM) improved radicle length under 0, 40 and 80 mM NaCl salinity levels as well as increased plumule length at the 0 and 40 mM NaCl salinity conditions.</span>