The Potential of Priming to Improve the Germination and Growth of Some Varieties of Wheat (Triticum durum Desf.)

Seed priming is a pre-germination treatment administered through various chemical, physical and biological agents, which induce mild stress during the early phases of germination. Priming facilitates synchronized seed germination, better seedling establishment, improved plant growth and enhanced yield, especially in stressful environments. The present work compares the effects of priming on the germination and tolerance of some Tunisian wheat varieties to saline stress, as evaluated by the germination percentage, germination index, coefficient of velocity, vigor index, seedling length, dry weight and seed water content. NaCl (100 mM) was used to induce salinity stress. Seeds of the sixth cultivar were primed with water (0 mM), sodium nitroprusside (0.06 mM), calcium silicate (8 mM), potassium nitrate (10 mM), wich not only improved the germination percentage but also considerably reduced germination time and increased germination index (GI), coefficient of velocity (CV) and vigor index indicating the potential for tolerating saline conditions. Seedling growth (seedling length, dry weight) and the water content of seeds primed with distilled water (H2O), sodium nitroprusside (SNP), calcium silicate (Si) and potassium nitrate (KNO3) were significantly greater than those of other non-primed seeds under saline conditions. Priming with different agents was effective, nevertheless, the best results were obtained with SNP, Si and KNO3. On the other hand, seed priming with various priming agents has proven to be effective in inducing salt tolerance in terms of germination parameters, seedling characteristics, and water content for six local commercial wheat cultivars.