Response of wheat cultivars to zinc application for seed yield and quality improvement

Abstract Zinc deficiency is a common nutritional problem in calcareous agricultural soils, resulting in reduced crop yield and performance. The effects of zinc sulphate (0 and 40 kg/ha) on seed yield, its components and seed element contents of 21 wheat cultivars were investigated. Zinc sulphate application increased plant height, leaf area index (LAI), flag leaf area, biomass, spike length, number of seeds per spike, seed weight and harvest index (HI). The increase in HI indicates the greater effect of zinc on seed production compared to plant biomass. In most of the cultivars, zinc sulphate application decreased the content of phosphorus and nitrogen in seeds and increased the content of iron and potassium. The cultivars showed significant differences in all the traits measured, indicating the existence of genetic diversity in the cultivars studied. In the second year, which was hotter and drier than the first year, zinc sulphate application reduced the damage caused by drought and heat stress and improved seed yield and quality. The regression fit showed that newer cultivars had lower yields in unfertilized conditions compared to old cultivars and showed their superiority in zinc fertilized conditions. It seems that the newer varieties require more fertilizer because they have been bred on fertile soils.