Mitigating the adverse effects of drought stress through seed priming and seed quality on wheat (Triticum aestivum L.) productivity

Drought stress, at reproductive phase in particular, severely reduces wheat yield but some agronomic techniques have the potential to overcome this damage. A field experiment was planned to evaluate the role of seed priming and seed size in drought tolerance of wheat. Bold (1000-seed weight 44.4 g) and small (1000-seed weight 22.4 g) sized seeds were soaked in CaCl₂ solution (osmopriming; ψs -1.25 MPa) while untreated dry seeds were taken as control. Crop was grown by using primed and untreated seeds under well-watered conditions till booting stage and then put under drought stress (50% of the field capacity) or control (100% of the field capacity) till biological maturity. Drought stress substantially decreased the wheat productivity due to significant reduction in allometric i.e. crop growth rate (CGR), leaf area index (LAI) and yield components. Moreover, osmoprimed seeds with CaCl₂ over dry seeds and large sized seeds over small sized seeds maintained their dominance due to early and uniform stand establishment, improving crop allometry and productivity due to notable expansion in entire yield related traits under well-watered and drought stress conditions. In conclusion, osmoprimed bold sized seeds may have a vital role in improving wheat production by early and uniform stand establishment, improving crop allometry and productivity due to considerable expansion in yield related traits under normal irrigated and drought stress conditions.