Movement of the xylem exudate of /sup 86/rubidium accumulated in the apex of corn roots

Journal Article · Mon Jan 01 04:00:00 EST 1979 · Plant Physiol.; (United States)

OSTI ID:5505571

Smith, R C

Apical segments of roots of corn (Zea mays, L.) were excised and mounted in experimental salt solutions containing /sup 86/RbCl and CaCl/sub 2/. Xylem exudates were collected hourly beginning at the 21st hour. At the 24th hour, experimental solutions were replaced with solutions of other chlorides (nonlabeled) of Ca/sup 2 +/ +- some monovalent cation. Following replacement of the labeled solutions, the rate of /sup 86/Rb/sup +/ release to the exudates from root segments declined by about the same proportional amount regardless of the initial steady-state output rate or the kinds of salts used to replace the RbCl. The content of /sup 86/Rb/sup +/ in the roots also declined with time, but to a relatively less degree. Loss of accumulated /sup 86/Rb/sup +/ to the various external solutions following replacement was less than 6% in 6 hours. It is concluded that movement of accumulated Rb/sup +/ to the exudate is dependent on the concentration of Rb/sup +/ in the root but is largely independent of exchange between accumulated ions and other ions in transit across the root.

• Research Organization: Univ. of Florida, Gainesville
• OSTI ID: 5505571
• Journal Information: Plant Physiol.; (United States), Journal Name: Plant Physiol.; (United States) Vol. 63:1; ISSN PLPHA
• Country of Publication: United States
• Language: English

Related Subjects

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54 ENVIRONMENTAL SCIENCES
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63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
ALKALI METAL ISOTOPES
ALKALINE EARTH METAL COMPOUNDS
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
CALCIUM CHLORIDES
CALCIUM COMPOUNDS
CALCIUM HALIDES
CEREALS
CHLORIDES
CHLORINE COMPOUNDS
CLEARANCE
DAYS LIVING RADIOISOTOPES
EXCRETION
GRAMINEAE
GRASS
HALIDES
HALOGEN COMPOUNDS
INTERMEDIATE MASS NUCLEI
ISOMERIC TRANSITION ISOTOPES
ISOTOPES
MAIZE
MINUTES LIVING RADIOISOTOPES
NUCLEI
ODD-ODD NUCLEI
PLANTS
RADIOISOTOPES
RADIONUCLIDE KINETICS
ROOTS
RUBIDIUM 86
RUBIDIUM ISOTOPES