Seed priming with salicylic acid for improving germination attributes and early growth of wheat under salinity stress

Seed priming with salicylic acid (SA) was tested as a strategy for improving germination of bread wheat (Triticum aestivum) cv. 'Tintoretto' under NaCl-induced stress. Salinity decreased germination percentage by 25 points and speed of germination by 1.53 times relative to normal conditions, whereas it increased mean germination time. Furthermore, salinity reduced the total dry weight of wheat seedlings by 48.5% and seedling vigor index by 62.5%. Lower content of chlorophyll-a (chl-a) and chlorophyll-b (chl-b) by 1.45 and 1.22 times, respectively, were found in wheat seedlings under salinity relative to normal conditions. Seed priming with SA (100 or 200 ppm for 24 h) promoted germination percentage and speed of germination under salinity relative to non-priming. Furthermore, SA priming promoted total dry weight and photosynthetic pigments content in salt-affected wheat seedlings. Values of mean productivity and harmonic mean indices in SA-primed seeds were on average 1.21 and 1.28 times, respectively, higher than those in non-primed seeds. SA-primed seeds showed lower values of productivity loss compared with non-primed seeds. Findings provide insights into the negative effects of salinity on wheat germination and seedling growth, as well as how seed priming with SA can mitigate those effects and improve wheat production in salinized environments.