Effective management of nutrient application is important part of the crop production puzzle and it seems that nano-fertilizers may have high potential for achieving sustainable crop production. A field experiment was carried out to investigate the effect of adding different nano-size and biological fertilizers on maize growth under various irrigation regimes. The experiment conducted under optimal irrigation level (up to ~50% field capacity) which is applied from the beginning of the reproductive period. Fertilizer’s treatments included control (Nf; no-fertilizer application), N biofertilizer (Bio-N), P biofertilizer (Bio-P), nanochelated B (Nano-B), nano-chelated Zn (Nano-Zn), complete nano-fertilizer (Nano-C) and conventional mineral NPK fertilizer. Bio-P was the best treatment in terms of grain yield, ear length, biological yield, number of the kernels per row, length of ear leaf and straw yield traits, while Nano-Zn was the best treatment for increase of protein content and Nf was the best treatment for increase of oil content. Bio-N was the best treatment in terms of leaf area, ear diameter and hundred grain weight, while Nano-B was the best treatment for plant height, harvest index, stem diameter, number of the row per ear and number of the kernels per ears traits. Nano-C and NPK are not outstanding for any of the traits. Nano-Zn had good effect on high yield and high protein content while nano-B was good for better performance of plant height, stem diameter, number of the row per ear, harvest index and number of the kernels per ears traits. Such an outcome could be used in the future to advise good recommendation strategies for recommendations for maize and other crops in other areas of the world.
