Agronomic biofortification of spring maize with zinc for enhanced productivity

Abstract

The deficiency of micronutrients is an expected trend among cereal crops that confines yield and nutritional value of grains. Agronomic biofortification is a viable option and practical way to maximize uptake and accumulation of Zn in maize grain and enhance productivity. Two experiments were carried out for this study. In first experiment the screening of ten maize hybrids (Hycorn-8288, 31-P-41, DATA-2236, DK-6142, SB-11, 32-B-33, P-1543, DATA-2237, DK-6525 and 32-F-10) to Zn fertilization (0 and 9 mg Zn kg-1 soil) was assessed in net house under CRD factorial arrangement. The most Zn efficient (DK-6525) and inefficient (Data-2236) maize hybrids against Zn fertilization were evaluated. While the second experiment was conducted to investigate the effect of different methods of Zn application on two different sowing dates (15 Feb and 05 March) on two maize hybrids (DK 6525 and Data 2236), which were selected on the basis of screening, at Agronomic Research Area, University of Agriculture Faisalabad Pakistan. The experiment was laid out in randomized complete block design (RCBD) with split split plot arrangement using three replications. It comprised of treatments viz. No Zn application (control), seed priming with Zn (0.5%), soil application of Zn using 18 kg ha-1, foliar application with Zn (0.5%), seed priming with Zn (0.5%) + foliar application with Zn (0.5%), soil application of Zn using 18 kg ha-1 + foliar application with Zn (0.5%) as ZnSO4. The net house study concluded that zinc enhanced the seedling fresh and dry weight, shoot zinc concentration and zinc uptake of maize hybrids. Among the ten maize hybrids DK-6525 performed the best under zinc application and zinc deficient conditions, but Data-2236 was found highly zinc inefficient. However, In field experiment maize hybrid DK-6525 with combined application of Zn as soil application (18 kg ha-1) and foliar spray (0.5%) showed significant improvement in growth, yield, and quality parameters during both years (2013 and 2014) of experimentation. The results further revealed that soil application (18 kg ha-1) and foliar spray (0.5%) also gave maximum gross and net income and benefit cost ratio during both years (2013 and 2014) of experimentation. The study suggested that DK-6525 should be sown during mid of February and besides using of recommended doses of NPK fertilizer, combined use of Zn as soil application (18 kg ha-1) with foliar application (0.5%) should be practiced for getting better quality and higher production of maize hybrids.