Agronomic bio-fortification and productivity of maize (Zea mays L.) through zinc application

A field experiment was conducted during the winter (rabi) season of 2018 and 2019 at instructional farm of Uttar Banga Krishi Viswavidyalaya, West Bengal, India, to find out a cost-effective method of zinc application for improving productivity and profitability of maize cv. ‘Kaveri 2018’ cultivation in randomized block design with 8 treatments and 3 replications. Soil application of 10 kg Zn/ha resulted in significantly tallest plant, maximum leaf-area index (LAI) and dry-matter accumulation. Yield attributes, viz. cob length, cob width, grains/row and grains/cob, were found highest with the application of 10 kg Zn/ha and showed 23.98 and 19.80% yield advantage over the control, which was followed by soil application of 5 kg Zn/ha, seed priming with 2% Zn solution and seed priming with 1% Zn solution + foliar application of 0.5% Zn at tasseling stage. Zinc concentration in grain was the highest (25 and 26.07 mg/kg) with soil application of 10 kg Zn/ha followed by seed priming with 2% Zn solution (21.33 and 23.60 mg/kg) and soil application of 5 kg Zn/ha (19.50 and 23.83 mg/kg) during both the years. Economic analysis revealed that, seed priming with 2% Zn solution fetched higher benefit: cost (B: C) ratio of 1.88 and 2.33 during 2018 and 2019, respectively, followed by soil application of 5 kg Zn/ha and soil application of 10 kg Zn/ha. Thus, to maintain the productive performance of hybrid maize cv. ‘Kaveri 218’ seed priming with 2% Zn solution may be used.