Abstract
Topped plants of tomato (Lycopersicon esculentum), cucumber (Cucumis sativus), corn (Zea mays), carrot (Daucus carota), and peanut (Arachis hypogaea) were treated with 0.5 to 50 micromolar Ni (containing 63Ni) in nutrient solutions. Xylem exudate was collected for 10 hours or, in the case of corn, for 20 hours at 5-hour intervals. Electrophoresis of nutrient solution distributed all Ni cathodically as inorganic Ni2+. Low concentrations of Ni in tomato exudate migrated anodically, presumably bound to organic anion (carrier). However, this carrier became saturated at about 2 micromolar Ni in exudate, and excess Ni ran cathodically. Most of the Ni in cucumber, corn, carrot, and peanut exudate ran anodically, and its migration rate was identical for all exudates. Peanut root sap contained 14 to 735 micromolar Ni. The anodic Ni carriers in root sap and exudate appear identical. The carrier in root sap became saturated near 100 micromolar Ni, as shown by cathodic streaking of Ni exceeding that concentration. It appears that all five species translocate low concentrations of Ni in the same anionic form.
Full text
PDF




Images in this article
Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- Tiffin L. O. Iron Translocation II. Citrate/Iron Ratios in Plant Stem Exudates. Plant Physiol. 1966 Mar;41(3):515–518. doi: 10.1104/pp.41.3.515. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Tiffin L. O. Iron translocation I. Plant culture, exudate sampling, iron-citrate analysis. Plant Physiol. 1966 Mar;41(3):510–514. doi: 10.1104/pp.41.3.510. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Tiffin L. O. Translocation of iron citrate and phosphorus in xylem exudate of soybean. Plant Physiol. 1970 Mar;45(3):280–283. doi: 10.1104/pp.45.3.280. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Tiffin L. O. Translocation of manganese, iron, cobalt, and zinc in tomato. Plant Physiol. 1967 Oct;42(10):1427–1432. doi: 10.1104/pp.42.10.1427. [DOI] [PMC free article] [PubMed] [Google Scholar]