Silicon alleviates adverse effect of drought stress induced by polyethylene glycol (peg 8000) on seed germination and seedling growth of durum wheat varieties

The effect of Silicon treatments on 11 durum wheat (Triticum durum Desf.) seed germination under in vitro drought stress conditions was studied. The laboratory experiment was performed using a factorial completely randomized design with three levels of drought stress (0, 100 and 200 g/l PEG8000) and five Silicon concentrations (0, 5, 10, 15 and 20 mg/l Si) with three replications for each treatment. Fresh weight, dry weight, germination percentage, seedling length and vigor index were measured under the experiment conditions. Variance analysis results (ANOVA) showed highly significant (p<0.001) differences between treatments and varieties for all traits. It was observed that PEG concentrations decrease seed germination and seedling growth traits and that adding Si mitigates PEG effects as a significant increase especially with highest Si concentrations (15 and 20 mg/l). Silicon increase fresh weight, dry weight, germination percentage, seedling length and vigor index by 25 %, 21.42 %, 12.67 %, 17.45 %, 164.67 % and 143.12 % when the Si concentration was 0 mg/l and 20 mg/l respectively. It is concluded that Si addition is beneficial to improve durum wheat seed germination and plant growth under drought stress.