Open AccessEffect of Glyphosate on Carrot and Tobacco Cells
Author(s) -
Lloyd C. Haderlie,
Jack M. Widholm,
F. W. Slife
Publication year - 1977
Publication title -
plant physiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 3.554
H-Index - 312
eISSN - 1532-2548
pISSN - 0032-0889
DOI - 10.1104/pp.60.1.40
Subject(s) - glyphosate , daucus carota , phenylalanine , glycine , amino acid , hydrolysate , tryptophan , nicotiana tabacum , tyrosine , biochemistry , aromatic amino acids , casein , chemistry , incubation , biology , food science , botany , hydrolysis , agronomy , gene
The growth of suspension-cultured carrot (Daucus carota L.) and tobacco (Nicotiana tabacum L. cv. Xanthi) cells was inhibited by glyphosate (N-[phosphonomethyl]glycine). This inhibition was reversed by adding combinations of phenylalanine, tyrosine, and tryptophan or casein hydrolysate. Casein hydrolysate and phenylalanine + tyrosine + tryptophan were the most effective treatments. Reversal of glyphosate-induced inhibition occurred only if the aromatic amino acids were added during the first 8 days of glyphosate incubation. Glyphosate uptake was not reduced when the aromatic amino acids or casein hydrolysate were added.Even though phenylalanine biosynthesis is a suggested site for glyphosate action, inhibitory levels of glyphosate did not lower free phenylalanine concentrations in carrot cells within 10 days. (14)C-Phenylalanine studies indicated that the metabolic pool size was, likewise, not decreased.In carrot cells total free amino acids increased within 6 hours after glyphosate addition. Cell protein levels declined within 48 hours following glyphosate treatment.Studies on (14)C-thymidine and (14)C-uridine incorporation were complicated by rapid metabolism of these compounds to (14)CO(2).