Abstract Purpose This study aimed to investigate the influence of a mix of manganese (Mn) and zinc (Zn) from soluble foliar fertilizers-based sulfates and EDTA chelates with fungicides-based emulsifiable concentrate and suspension concentrate for Powdery Mildew control. Methods From greenhouse conditions, nutrient absorption in soybean plants ( Glycine max L.) at the V3 and R1 growth stages was quantified using portable and benchtop X-ray fluorescence (pXRF) equipment to determine absorption dynamics over time. Additionally, synchrotron-based imaging was employed to analyze elemental distribution across the leaf surface following application. Powdery Mildew severity was assessed 15 days post-application to evaluate disease control efficacy. Results Mn and Zn were more effectively absorbed when applied as sulfates and without mixture. However, when EDTA-chelated Mn and Zn were combined with emulsifiable concentrate fungicides, absorption rates surpassed those observed with fertilizers applied alone. Synchrotron analysis revealed complete diffusion of Mn and Zn throughout the treated leaf area within 48 h. Furthermore, fungicides were effective in disease control when applied both alone and in combination with foliar soluble fertilizers. Conclusion Tank mix of soluble fertilizers and fungicides interferes with nutrient absorption, but under greenhouse conditions, no negative effects were observed on disease control efficacy.
Silva et al. (2026) studied this question.