The effect of seed priming treatments and foliar application of vitaspirin and urea on wheat grain yield under dryland conditions

Drought is a major obstacle for wheat production around the world. Seed priming and foliar nutrition spray at various stages of growth have both been shown to be beneficial in lowering stress and improving wheat grain production. For this reason, this experiment was conducted in the form of split plots in a randomized complete block design with two factors including seed priming (Main factor) and foliar application (Sub-factor), and 3 replications during the 2018-2019 and 2019-2020 cropping seasons. Eight seed priming treatments including control (without seed priming), water (hydro-priming), urea (2%), zinc sulfate (0.6%), potassium chloride (1%), calcium chloride (1.4%), vitaspirin (1 g L-1), and cytokinin (50 mg L-1) were randomized on the main plot, and 3 foliar application treatments including control (without foliar application), urea (4%), and vitaspirin (0.1%) were randomized on a sub-plot. The results showed that the thousand kernel weight had not had much effect on grain yield in this experiment. Furthermore, treatments that increased the number of grains had a positive impact on enhancing grain yield. In the 2020-2019 cropping season, none of the seed priming treatments enhanced grain yield because of temperature and rainfall constraints. This demonstrated the role of early growth conditions in the effectiveness of seed priming treatments. As a result, seed priming treatments without foliar application under dryland conditions cannot be recommended due to the unpredictability of weather conditions. In both cropping seasons, seed priming with calcium chloride + foliar application of vitaspirin was one of the top three treatments in terms of grain yield.