Compartmental analysis of roots in intact rapidly-growing Spergularia marina and Lactuca sativa: partial characterization of the symplasms functional in the radial transport of Na/sup +/ and K/sup +/

Thesis/Dissertation · Thu Jan 01 00:00:00 EST 1987

OSTI ID:6602779

Lazof, D B

Techniques of compartmental analysis were adapted to the study of intact roots of rapidly-growing Spergularia marine and Lactuca sativa. Using large numbers of plants short time-courses of uptake and chase, /sup 42/K/sup +/ and /sup 22/Na/sup +/ transport could be resolved, even during a chase following a brief 10 minute labeling period. The use of intact plant systems allowed distinction of that portion of the isotope flux into the root, associated with the ion-conducting symplasms. A small compartment, which rapidly (t/sub .5/ < 1 min) exchanges with the external medium was implicated in the radial transport of N/sup +/, accounting for the observed obtention of linear translocation rates within minutes of transferring to labeled solution. The ion contents of this compartment varied in proportion to the external ion concentration. When K/sup +/ was at a high external concentration, labeled K/sup +/ exchanged into this same symplasm, but chasing a short pulse indicated that K/sup +/ transport to the xylem was not through a rapidly-exchanging compartment. At physiological concentrations of K/sup +/ the evidence indicated that transport of K/sup +/ across the root proceeded through a compartment which was not exchanging rapidly with the external medium. The rise to a linear rate of isotope translocation was gradual and translocation during a chase, following a brief pulse,was prolonged, indicating that this compartment retained its specific activity for a considerable period.

• Research Organization: Illinois Univ., Urbana (USA)
• OSTI ID: 6602779
• Resource Relation: Other Information: Thesis (Ph. D.)
• Country of Publication: United States
• Language: English

Related Subjects

59 BASIC BIOLOGICAL SCIENCES
POTASSIUM COMPOUNDS
MEMBRANE TRANSPORT
SODIUM COMPOUNDS
PLANTS
POTASSIUM 45
ROOTS
SODIUM 22
TRACER TECHNIQUES
TRANSLOCATION
ALKALI METAL COMPOUNDS
ALKALI METAL ISOTOPES
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
BETA-PLUS DECAY RADIOISOTOPES
INTERMEDIATE MASS NUCLEI
ISOTOPE APPLICATIONS
ISOTOPES
LIGHT NUCLEI
MINUTES LIVING RADIOISOTOPES
NUCLEI
ODD-EVEN NUCLEI
ODD-ODD NUCLEI
POTASSIUM ISOTOPES
RADIOISOTOPES
SODIUM ISOTOPES
YEARS LIVING RADIOISOTOPES
551001* - Physiological Systems- Tracer Techniques