Response to Foliar Micronutrients Application: Oil Content, Fatty Acid Profiling, Growth and Yield Attributes in Sunflower Hybrids

Abstract Micronutrient deficiency is widespread in alkaline soils of Pakistan which ultimately affect the yield and quality of sunflower oil. The current study was designed to investigate the combined as well as the sole effect of micronutrient application on the growth and yield attributes, and fatty acids profiling of selected sunflower hybrids. A field trial was conducted in sub-humid climatic conditions and two sunflower hybrids (FMC-1 and Parsun-3) were grown at the University of Haripur’s research farm. Micronutrients were applied through the foliar application at the start of the bud growing stage and before the flowering stage i.e., after 30 and 55 days of sowing. The application of micronutrients resulted in significant variation in agronomic parameters of sunflower hybrids. Molybdenum among the sole application and in combination treatments Zn, B, and Mo increased the growth traits of sunflower genotypes, while application of Zn and Mo (among sole application), and combination of Zn, B, and Mo increased the yield attributes. Oil content was highest in the combination of three micronutrients (Zn, B, and Mo) application followed by the Zn and B application individually. Sole micronutrients application also increased oil contents in both hybrids. Zinc application resulted in an increase of unsaturated fatty acids and a decrease in saturated fatty acids, while the B increased the oleic acid and stearic acid content and decreased the linoleic acid and palmitic acid contents. Among the varieties, FMC-1 has significantly achieved a higher yield than the Parsun-3. It is concluded from the research that Zn application increased the beneficial (poly- and mono-unsaturated) fatty acids and decreased the harmful (saturated) fatty acids. Zinc application @ 2 kg ha1 is recommended for good quality oil production.