Determination of Ca, Mg, K, Mn, Cu, Zn, Fe, and P in coffee, soybean, corn, sunflower, and pasture grass leaf tissues by a HCl extraction method

Abstract

Abstract Chemical analyses for Ca, Mg, K, Cu, Fe, Mn, and Zn in leaf tissue digested in HNO3‐HClO4 acid were compared to the analyses of HCl extracts of leaf tissue. The leaf tissue includes leaves from coffee, soybean, corn, sunflower, and forage grass. The chemical analyses for Ca, Mg, K, Cu, Mn, and Zn were essentially identical for the digestion and extraction procedures. However, the HCl extraction procedure recovered 69% and 50%, respectively, of the P and Fe mineralized with the HNO2‐HClO4 digestion. The HCl extraction procedure is recommended for routine analyses because of its simplicity, low cost, and safety characteristics.