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

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.

Key words:

• Plant material analysis
• multi‐element analysis
• non‐digestion
• nitric‐perchloric digestion