Plant Physiol. Illumina
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
QUICK SEARCH:   [advanced]


     

Plant Physiology 77:718-721 (1985)
© 1985 American Society of Plant Biologists

This Article
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in Web of Science
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrow reprints & permissions
Citing Articles
Right arrow Citing Articles via CrossRef
Right arrow Citing Articles via Web of Science (22)
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Morgan, M. A.
Right arrow Articles by Jackson, W. A.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Morgan, M. A.
Right arrow Articles by Jackson, W. A.
Agricola
Right arrow Articles by Morgan, M. A.
Right arrow Articles by Jackson, W. A.
Articles

p-Fluorophenylalanine-Induced Restriction of Ion Uptake and Assimilation by Maize Roots 1

M. A. Morgan2, Richard J. Volk and William A. Jackson

Department of Soil Science, North Carolina State University, Raleigh, North Carolina 27695-7619

Roots of decapitated maize seedlings (Zea mays L.) were exposed for 12 hours to 1.0 millimolar KNO3 (98.5 atom per cent 15N) in the presence and absence (control) of 0.1 millimolar p-fluorophenylalanine (FPA), an analog of the amino acid phenylalanine. FPA decreased nitrate uptake but had little effect on potassium uptake. In contrast, accumulation of both ions in the xylem exudate was greatly restricted. The proportion of reduced 15N-nitrogen that was translocated at each time was also restricted by FPA. These observations are interpreted as indicating that synthesis of functional protein(s) is required for nitrate uptake and for transport of potassium, nitrate, and reduced-15N from xylem parenchyma cells into xylem elements. The effect of FPA on nitrate reduction is less clear. Initially, FPA limited nitrate reduction more than nitrate uptake, but by 8 hours the cumulative reduction of entering nitrate was similar (~35%) in both control and FPA-treated roots. A relationship between nitrate uptake and nitrate reduction is implied. It is suggested that nitrate influx regulates the proportion of nitrate reductase in the active state, and thereby regulates concurrent nitrate reduction in decapitated maize seedlings.

2 Present address: Department of Agricultural Chemistry and Soil Science, University College, Belfield, Dublin 4, Ireland.

1 Supported by National Science Foundation Grant PCM 81-18661. Paper No. 9312 of the Journal Series of the North Carolina Agricultural Research Service, Raleigh, NC.






HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
ASPB Publications PLANT PHYSIOLOGY® THE PLANT CELL
Copyright © 1985 by the American Society of Plant Biologists