Zinc nano-fertilization enhances wheat productivity and biofortification

Zinc (Zn) malnutrition has emerged as one of the major health challenges in developing nations across the globe. Development of Zn management protocols in staple food crops using modern scientific tools to enhance Zn concentration in grains along with augmented crop yields became utmost necessary. In this context a 2-year experiment was carried out to assess the effects of zinc oxide nanoparticles (ZnO-NPs) vis-a-vis bulk zinc sulfate (ZnSO4) on wheat growth, yield and Zn concentration in plant parts. Four levels of application of ZnO-NPs (0, 20, 25 and 30 mg kg-1) were compared with ZnSO4 (equal to Zinc concentration in ZnO-NPs). Results revealed that seed vigor was significantly (p <0.05) higher under 25 and 30 mg kg-1 soil ZnO-NPs treatments over ZnSO4. Among the crop yield parameters such as tillers (plant-1), grain weight (plant-1), biomass (plant-1) and grain yield were significantly (p <0.05) higher under ZnO-NPs 25 mg kg-1 treated soil as compared to any other treatment. Zinc concentration in grains increased with dose of ZnO-NPs and it was significantly more than ZnSO4 treated soil at each treatment level. ZnO-NPs and ZnSO4 treatments did not affect photosynthetic rate and chlorophyll (SPAD) content significantly. In conclusion, 25 mg kg-1 ZnO-NPs application could be recommended in wheat cultivation to improve growth, yield and grain Zn biofortification.