Influence of exogenously sprayed growth regulators at different concentrations on grain biochemical constituents and yield traits of bread wheat

Plant growth regulators play an essential role in plants' biochemical processes.In this study, foliar spray was applied using three growth regulators, gibberellic acid (GA3), naphthalene acetic acid (NAA), and 6-benzyl amino purine (BAP), to investigate their effects on wheat (Triticum aestivum L.) 'Giza-171' yield traits and grain biochemical constituents, including sugars, carbohydrates and protein.The assessed growth regulators (GA3, NAA, and BAP) were applied at 100 and 150 mg L -1 concentrations.The results indicated significant improvements in wheat grain yield and 1000-grain weight, which increased by 15.40% and 24.78%, respectively, using GA3 at 150 and 100 mg L -1 .In addition, the highest contents of protein and carbohydrates were observed with samples treated by the foliar application of NAA at 150 mg L -1 and BAP at 100 mg L -1 , respectively.The fat content in wheat grains increased by 1.97% and 2.73% with foliar spray with 150 mg L -1 NAA and 100 mg L -1 BAP, respectively.The lipid profile showed cis-linoleic acid was the primary fatty acid, followed by palmitic acid; the content of linoleic acid slightly increased with GA3 treatment to 50.42%, while palmitic acid significantly increased with 100 mg L -1 NAA.The total saturated and unsaturated fatty acids recorded 33.64% and 66.30%, respectively; the 150 mg L -1 NAA treatment had the lowest saturated fatty acid content.The SDS-PAGE profiles showed that growth regulators significantly enhanced the wheat protein where new bands appeared, especially in 100 mg L -1 GA3 and 100 mg L -1 BAP treatments.The applied growth regulators improved wheat yield, contents of some compounds, and nutritional value.