Iron supply to tobacco plants through foliar application of iron citrate and ferric dimerum acid

Abstract

Experiments to assess the re‐greening and the distribution of leaf‐applied iron (Fe) within the aerial organs were developed with tobacco (Nicotiana tabacum L.) plants. Fe (III)‐citrate and Fe‐dimerum acid were applied to a part of the leaf and plant re‐greening was monitored for 6 weeks after treatment. Fluid Fe increments associated with foliar Fe application were measured within 3 days after application. Fe distribution from the site of application within the leaf and the untreated above‐ground plant parts was evaluated. Leaf fluid Fe concentration was determined by a novel procedure based on Fe chelation by desferrioxamine E and high performance liquid chromatography separation on a reversed‐phase column. The ferrioxamine E method enabled accurate determination of small amounts of Fe present in leaf fluid. Foliar Fe‐dimerum acid and Fe (III)‐citrate treatment to chlorotic tobacco plants induced new growth re‐greening. It was concluded that the applied Fe‐containing compounds penetrated the leaf, were distributed within the plant and that Fe supplied as both complexes could be utilized by the plant cell.