Abstract
The synthetic growth regulator NC 9634, [(3-phenyl-1,2,4-thiadiazol-5-yl)thio] acetic acid (NC 9634) was shown to have anti-auxin properties in bioassay tests. The inhibition of wheat coleoptile extension growth by concentrations of NC9634 up to 260 μM was completely overcome by 60 μM IAA, 50 μM NAA or 50 μM 2,4-D. In cress root tests 2.6 × 10−7 M NC 9634 stimulated root elongation and relieved the growth inhibiting effect of 2,4-D. Extension growth of intact apple shoots was inhibited by NAA, which proved lethal at concentrations above 6.25 × 10−4 M. NC 9634 applied in combination with the NAA, reduced this growth inhibiting effect and prevented death of shoots sprayed with high auxin concentrations.
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Abbas, M.F., Quinlan, J.D. & Buckley, W.R. Antagonistic interaction between auxins and the growth regulator NC 9634. Plant Growth Regul 2, 3–8 (1984). https://doi.org/10.1007/BF00024090
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DOI: https://doi.org/10.1007/BF00024090