Strategic sulphur-micronutrient application reduces plant stress while improves maize yield stability, grain nutrient-density and soil microbial health across diverse ecologies

Micronutrient deficiencies are a major global-health challenge driven by inadequate dietary intake. Nutrient application to the soil for cereals like maize (Zea mays L.) offer a promising solution. Five combinations of Zn-embedded sulphur (Zn-ES) and multi-micronutrient embedded sulphur (MM-ES) with varied level of Recommended Doses of Fertilizers (RDF), two treatments of organic materials with 75 % RDF were evaluated relative to RDF and control. Multi-location trials were conducted in 2023 and 2024 at semi-arid ecologies of New Delhi and Karnal and temperate-highlands of Shimla. The mean maize grain yield was 5.65, 5.80 and 5.25 t ha −1 in New Delhi, Karnal and Shimla, respectively. The GGE biplot analysis revealed that application of Sulphur (S), Zn-ES and MM-ES with 100 % RDF (T 6 ) resulted in highest yield at Karnal surpassing New Delhi (+4.9 %) and Shimla (+8.9 %) with greater stability at New Delhi in 2024 and Karnal in 2024. Furthermore, concentration of sulphur and micronutrients (Fe, Mn, Zn and Cu) were increased in T 6 by 13–54.3 %. The remobilization efficiency of S (+22.6 %) and micronutrients (9.7–71.2 %) remained highest under T 6 and T 4 , respectively. Harvest indices of S and micronutrients were improved by 10.4–89.3 % and 1.9–41 % relative to RDF. GGE biplot analysis in terms of micronutrient remobilization further exhibited consistency of T 6 . Highest soil microbial-biomass C (+6.92 %), acid phosphatase (+16.78 %), alkaline phosphatase (+6.77 %) and dehydrogenase (+35.2 %), were noted at Karnal under T 6 . The T 6 enhanced RWC, SPAD and NDVI value by 6, 29.2 and 27.3 % and reduced proline content significantly. This study demonstrates that co-application of RDF with micronutrients optimizes maize productivity and biofortification, offering a sustainable strategy to address micronutrient malnutrition in line with ‘One Health’ framework. • Co-application of RDF and micronutrients enhanced grain yield and nutrient biofortification. • Split application of nutrients increased the nutrient enrichment in grain. • Co-application of micronutrients along with RDF improved remobilization efficiency and harvest indices. • Combined application of RDF and micronutrient demonstrated enhanced soil microbial activity and physiological parameters.