Abstract
A technique was developed for estimating penetration of P32 across roots of intact plants (Phaseolus vulgaris) by measuring the level of isotope in the xylem stream. Penetration was defined as movement from the root surface to the xylem sap. The xylem sap measurement for P32 was made in the stem as the material ascended the plant in the transpiration stream. Stems were held near 0° to arrest metabolic concentration of isotope adjacent to the xylem column. A 3 layer environment control system was constructed to allow stem chilling in a manner that would not interfere with the environments of the roots or foliage. Despite these precautions, some extra-xylary build-up of 32P occurred in the chilled stem. The mathematical function of the extra-xylary fraction was derived, and the difference between this value and total P32 in the stem represented xylem sap isotope.
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Selected References
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- Bowling D. J. Effect of ringing on potassium uptake by Ricinus communis plants. Nature. 1965 Apr 17;206(981):317–318. doi: 10.1038/206317b0. [DOI] [PubMed] [Google Scholar]
- Hodges T. K., Vaadia Y. Uptake and Transport of Radiochloride and Tritiated Water by Various Zones of Onion Roots of Different Chloride Status. Plant Physiol. 1964 Jan;39(1):104–108. doi: 10.1104/pp.39.1.104. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Wiebe H. H., Kramer P. J. Translocation of Radioactive Isotopes from Various Regions of Roots of Barley Seedlings. Plant Physiol. 1954 Jul;29(4):342–348. doi: 10.1104/pp.29.4.342. [DOI] [PMC free article] [PubMed] [Google Scholar]