Foliar application of zinc enhances the grain zinc concentration, whereas the soil application improves the grain yield of finger millet (Eleusine coracana L.)

• Published in: Indian journal of plant physiology Vol. 28; no. 4; pp. 513 - 520
• Main Authors: Nanja Reddy, Y. A., Narayana Reddy, A. B., Nirmalakumari, A., Patro, T. S. S. K., Subba Rao, M., Prabhakar, Gowda, M. V. C.
• Format: Journal Article
• Language: English
• Published: New Delhi Springer India 01.12.2023; Springer Nature B.V
• Subjects: Agricultural production; Arid regions; Arid zones; Biomedical and Life Sciences; Cell Biology; Cereals; Crop yield; Crops; Eleusine coracana; Flowering; Fodder; Foliar applications; Food; Forage crops; Genetic engineering; Genetically altered foods; Grain; Human populations; Life Sciences; Malnutrition; Millet; Original Article; Plant Biochemistry; Plant breeding; Plant Ecology; Plant Genetics and Genomics; Plant Physiology; Plant Sciences; Semi arid areas; Semiarid lands; Soil improvement; Soils; Zinc; Zinc sulfate; India; Grain zinc; Foliar application; Soil application; Finger millet; Grain yield
• ISSN: 2662-253X; 0019-5502; 2662-2548; 0974-0252
• DOI: 10.1007/s40502-023-00747-3

Globally 1/3rd of the human population is at the risk of zinc malnutrition concerning the development and well-being. The major cereal food crops are poor in zinc concentration. Plant breeding and genetic engineering strategies have improved the grain zinc content of major crops in India. Of the cereals, finger millet is an important staple food and fodder crop in semi-arid regions of Africa and Asia and has 2.5–3.0 mg of zinc/100 g grain against the requirement of 15 mg/day/adult. The immediate solution could be agronomic bio-fortification. The present study explored the soil and foliar-applied zinc to improve the grain zinc content by conducting experiments in south India. The results revealed that, although soil has nearly adequate native zinc concentration, the soil-applied zinc at the time of planting (ZnSO 4 7H 2 O @ 12.5 kg/ha) increased the mean grain yield across the locations by 14.2% compared to no-application of zinc. While the foliar-applied zinc (ZnSO 4 7H 2 O @ 0.5%) increased the grain yield by 6.7–9.3% compared to no-application of zinc. The foliar-applied zinc (twice, at the time of flowering and 15–20 days after 1st spray) increased the mean grain zinc content across the locations by 31.3%, and it was only 4.7% by soil application compared to no-zinc application. The foliar-applied zinc (ZnSO 4 7H 2 O @ 0.5%, twice) increased the grain zinc per hectare by 43.5%. The recovery of externally applied zinc by the grain was 12.2–14.1% in the foliar application compared to 4.1% in the soil-applied zinc.