Response of Ficus benjamina and Dracaena marginata to Iron Stress

in Journal of the American Society for Horticultural Science
View More View Less
  • 1 Department of Horticultural Sciences, Texas A&M University, College Station, TX 77843

Ficus benjamina L. and Dracaena marginata Lam. were grown in a modified Hoagland's nutrient solution containing either 0, 0.22 or 5.52 mg Fe3+/liter (HEEDTA or EDTA). F. benjamina grew well at all Fe levels and showed mild chlorosis only at 0 mg Fe/liter. For D. marginata, growth decreased and chlorosis increased as solution Fe level decreased. F. benjamina exhibited a high capacity for Fe3+ reduction, which increased as Fe level decreased, reaching a maximum below 0.06 mg·liter-1 D. marginata exhibited a low capacity for Fe3+ reduction, which was slightly enhanced at 0.1 to 0.15 mg·liter-1. In both species, reduction occurred in the presence of roots, with minimal reduction in their absence. This result indicates that Fe3+ is reduced at the root surface and not by reductants released into the solution. F. benjamina increasingly lowered pH as solution Fe decreased, and always lowered pH more than D. marginata at all Fe levels. Total and extractable Fe concentration of leaves did not correlate well with chlorosis, whereas total Fe content per plant correlated highly with chlorosis. Chemical names used: N-hydroxyethyl-ethylenediamine-triacetic acid (HEEDTA), ethylenediamine tetraacetic acid (EDTA).

All Time Past Year Past 30 Days
Abstract Views 0 0 0
Full Text Views 158 27 2
PDF Downloads 246 79 8