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Article
Glyphosate Effects on Carbon Assimilation, Ribulose Bisphosphate Carboxylase Activity, and Metabolite Levels in Sugar Beet Leaves
Plant Physiology
  • Jerome C. Servaites
  • Michelle A. Tucci
  • Donald R. Geiger, University of Dayton
Document Type
Article
Publication Date
10-1-1987
Abstract
Application of a 17-millimolar solution of glyphosate (GLP) to sugarbeet (Beta vulgaris L.) leaves resulted in an immediate and rapid Dec.line in the level of ribulose bisphosphate (RuBP). Phosphoglyceric acid level began to Dec.rease about 2 hours following the Dec.line in RuBP level. Photosynthesis rate Dec.lined linearly with RuBP level, but only when the RuBP level had Dec.reased to about twice the RuBP carboxylase active site concentration. This occurred about 4 hours following GLP-application. At this time starch synthesis also Dec.lined abruptly. The activation state of RuBP carboxylase did not change for 8 hours following GLP application and then Dec.reased slightly from 70 to 50% when the RuBP level fell below the RuBP carboxylase active-site concentration. Triose-phosphate, hexose-phosphate, and adenylate energy charge did not change for 8 hours following GLP-application. These data indicate that GLP induced a depletion of carbon or phosphate or both from the photosynthetic carbon reduction cycle, reducing the rate of regeneration of RuBP, photosynthesis, and starch synthesis, while having little effect upon the rate of sucrose synthesis and transport.
Inclusive pages
370-374
ISBN/ISSN
0032-0889
Publisher
American Society of Plant Biologists
Peer Reviewed
Yes
Disciplines
Citation Information
Jerome C. Servaites, Michelle A. Tucci and Donald R. Geiger. "Glyphosate Effects on Carbon Assimilation, Ribulose Bisphosphate Carboxylase Activity, and Metabolite Levels in Sugar Beet Leaves" Plant Physiology Vol. 85 (1987)
Available at: http://works.bepress.com/donald_geiger/34/