Chemical nature of manganese in the leaves of manganese accumulator plants

Abstract

Abstract The chemical nature of Mn in the leaves of Acanthopanax seiadophylloides, Ilex crenata var. paludosa and Kalopanax pictus was investigated. Successive extraction of freeze-dried and fresh leaf sam pies with various solvents showed that the major portion of Mn (>90%) was extractable with water and 0.2 M HCl. Electron probe X-ray microanalysis was performed with the fresh leaf tissues of Mn hyper accumulator A. seiadophylloides, before and after shaking with distilled water, 80% methanol and 1 M HCl. Water removed large parts of Mn in the tissue as a whole except in the region of the epidermis. A negligible amount of Mn was removed by 80% methanol; on the other hand, 1 M HCl removed almost all of the Mn in the tissues. Paper electrophoretic experiments conducted with water and 0.2 M HCl extracts using pyridine-acetic acid buffer (pH 6.5) indicated that Mn in the extracts behaved similarly to Mn2+, presumably due to the labile nature of Mn components in the tissues.