Influence of foliar application of biostimulants and micronutrients on the growth and yield dynamics of winter maize (Zea mays L.)

Abstract

The effect of foliar application of biostimulants and micronutrients on the growth, physiological traits, yield attributes and productivity of winter maize was evaluated in a field experiment at the Crop Research Centre, Institute of Technology and Management (ITM) University, Gwalior, Madhya Pradesh during the rabi seasons of 2024–25 and 2025–26. The experiment was laid out in a randomised block design (RBD) with 16 treatments and 4 replications. The treatments included individual and combined foliar applications of chitosan, seaweed extract, protein hydrolysates, iron (Fe), zinc (Zn) and a consortium comprising all the biostimulants and micronutrients. The consortium treatment (chitosan + seaweed extract + protein hydrolysates + Fe + Zn + iodine (I)) was found to significantly increase the growth, physiological attributes, yield components and productivity of winter maize. It recorded the highest crop growth rate (34.07 and 35.49 g m-2 day-1), leaf area index (LAI) (3.66 and 3.76), chlorophyll content (56.63 and 58.17 soil and plant analysis development (SPAD) units), grain yield (6.4 and 6.6 t ha-1), stover yield (13.1 and 13.4 t ha-1) and biological yield (19.5 and 20.0 t ha-1) during 2024–25 and 2025–26 respectively. However, the combined micronutrient treatment (Fe + Zn + I) did not significantly differ from the consortium treatment in most growth and yield parameters. The results demonstrate that foliar application of biostimulants and micronutrients enhances winter maize productivity by improving canopy development, chlorophyll content and biomass accumulation. The consortium treatment could be used for maximising productivity while the Fe + Zn + I treatment is a cost-effective option for agronomic biofortification under semi-arid agro-ecological conditions.