Optimization of Soil and Foliar Zinc and Iron Application for Enhanced Growth and Yield of Mungbean under Agronomic Biofortification in an Arid Region

Micronutrient malnutrition remains a major challenge in many developing countries where cereal-based diets constitute the primary source of nutrition. Iron (Fe) and zinc (Zn) are essential micronutrients that play critical roles in the physiological and metabolic functions of both plants and humans. The present study was conducted to evaluate the effects of different Zn and Fe application methods on growth, and yield of mungbean. A field experiment was carried out during the Kharif season (July 2022, July 2023) at the Instructional Farm of Agronomy, Agriculture University, Jodhpur, Rajasthan. The field experiment followed a split-split plot design (SSPD) comprised in main plots two mungbean varieties viz GM 7 and GM 4. The sub-plots were assigned three iron fortification levels namely, Control (Fe ₀ ), 20 kg FeSO ₄ ha ^− 1 (SA) + 0.5% FeSO ₄ foliar application at flower initiation (FI) and pod formation (PF) stage (Fe ₁ ), 25 kg FeSO ₄ ha ^− 1 soil application (SA) + 0.5% FeSO ₄ foliar application at FI and PF stages (Fe ₂ ) and sub-sub plots incorporated with Control (Zn ₀ ), seed inoculation (SI) with ZSB + 15 kg ZnSO ₄ ha ^− 1 (SA) + 0.5% ZnSO ₄ (FA) (Zn ₁ ), ZSB (SI) + 20 kg ZnSO ₄ ha ^− 1 (SA) + 0.5% ZnSO ₄ (FA) (Zn ₂ ), ZSB (SI) + 25 kg ZnSO ₄ ha ^− 1 (SA) + 0.5% ZnSO ₄ (FA) (Zn ₃ ). The results demonstrated that the combined application of Zn ₂ and Fe ₁ produced the greatest plant height, accumulation of dry matter, well as the highest number of branches plant ^− 1 . Yield parameters, including biological yield and seed yield improved significantly with micronutrient application. The highest biological yield (3086 kg ha⁻¹), (2948 kg ha⁻¹) (3021 kg ha⁻¹) and seed yield (1076 kg ha⁻¹, 1025 kg ha⁻¹, 1052 kg ha⁻¹) with V ₂ , Fe ₁ and Zn ₂ treatments, respectively were recorded significantly higher results. These findings demonstrate the potential Zn and Fe application as an efficient agronomic biofortification strategy to improve both the growth and yield of mungbean, thereby contributing to sustainable crop production and nutritional security.