Agro-Biofortification of Zinc and Iron in Wheat Grains

Zinc (Zn) and Iron (Fe) are essential micronutrients for both human and plants, but their deficiency is prevalent in the world, especially in developing countries including India and Pakistan. Therefore, zinc and iron biofortification of wheat and other cereal crops is being urgently addressed and highly prioritized as a research topic. Thus, a field study was planned in a silty-loam soil under conventional tillage, located at Peshawar, Khyber Pakhtunkhwa, Pakistan, in winter 2016-2017 to examine the influence of foliar zinc rates (0.1, 0.2, 0.3 and 0.4% ZnSO4.7H(2)O) and foliar iron rates (0.5, 1, 1.5 and 2% FeSO4.7H(2)O) on physiology, phenology, yield indices and grain Zn and Fe contents of wheat. The results specified that leaf area per tiller, flag leaf area, productive tillers, yield components, biomass yield, grain Zn and Fe contents were significantly improved with various foliar Zn and Fe levels. The plants fertilized with 0.3% Zn and 1% Fe exhibited higher grain yield. Higher grain Zn content was observed in plants fertilized with foliar Zn at 0.4% and Fe at 0.5%. Higher grain Fe content was noted in the plants fertilized with 0.1% Zn and 2% Fe. It can be concluded that the plants fertilized with 0.3% foliar Zn and 1% Fe resulted in improved yield components and yield, whereas the plants fertilized with 0.1% Zn and 2% Fe showed an improved wheat grain quality (Zn and Fe content). Hence, foliar fertilization of 0.3% Zn and 1% Fe is recommended for higher wheat yields and better grain quality under the edaphoclimatic conditions studied.