Translocation of Iron Citrate and Phosphorus in Xylem Exudate of Soybean
AUTOR(ES)
Tiffin, Lee O.
RESUMO
Soybean plants, Glycine max (L.) Merrill, in standard solution received 2.5 μm ferric ethylenediamine di(o-hydroxyphenylacetate (FeEDDHA) and 0 to 128 μm phosphorus. Their stem exudates contained: 32 to 52 μm Fe, 120 to 5000 μm P, and 120 to 165 μm citrate. Electrophoresis of exudates with high P caused Fe trailing that precluded identification of any major form of Fe. Exudate with low P gave an anodic band of Fe citrate as the major Fe compound. Phosphate added to exudate in vitro depressed the Fe citrate peak and cause Fe trailing. EDDHA added to exudate in vitro pulled Fe from Fe citrate; citrate then migrated as a slower form and Fe migrated as FeEDDHA. A modified preculture system, involving 2-day renewals of 0.2 μm FeEDDHA with 3.2, 9.6, or 16 μm P and low levels of other ions, controlled pH depression and produced considerable change in citrate and P levels. The exudates contained: 45 to 57 μm Fe, 200 to 925 μm P, and 340 to 1025 μm citrate. The high citrate was from plants grown with low P. The major form of Fe in the exudates was Fe citrate. This is probably the form translocated in the plants.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=396397Documentos Relacionados
- Translocation of Nickel in Xylem Exudate of Plants
- A naturally occurring chelate of iron in xylem exudate 12
- Iron Stress as Related to the Iron and Citrate Occurring in Stem Exudate 1
- Metal Complexation in Xylem Fluid 1: I. CHEMICAL COMPOSITION OF TOMATO AND SOYBEAN STEM EXUDATE
- Effect of Iron on the Transport of Citrate into the Xylem of Soybeans and Tomatoes