Dependency of Iron Reduction on Development of a Unique Root Morphology in Ficus benjamina L. Academic Article uri icon


  • The activity of the Fe(3+) reductase of excised adventitious roots of Ficus benjamina L., grown in hydroponic culture without iron, was determined by a colorometric assay simplified by the use of a microplate reader. Reductase activity remained the same from pH 4.5 to 6.5 and decreased sharply above pH 6.5. Acetate buffer inhibited reduction. During early stages of root growth, excised roots did not exhibit Fe(3+) reductase activity. After several weeks and extensive root system development, Fe(3+) reduction still was not detectable in primary roots, but intermediate and high rates of reduction occurred in lateral and newly formed root clusters, respectively. Clustered roots only developed on plants grown at 0 or very low (<1 micromolar) iron. Microscopic examination revealed the root cluster to be composed of up to 30 lateral roots, usually less than 1 millimeter in diameter and 1 centimeter in length, that were completely covered with root hairs.

published proceedings

  • Plant Physiol

author list (cited authors)

  • Rosenfield, C. L., Reed, D. W., & Kent, M. W.

citation count

  • 33

complete list of authors

  • Rosenfield, CL||Reed, DW||Kent, MW

publication date

  • April 1991