phytohormone Bot.
(faɪtəʊˈhɔːməʊn)
[ad. G. phytohormon (Kögl & Smit 1931, in K. Akad. von Wetenschoppen te Amsterdam: Proc. Sect. Sci. XXXIV. 1416): see phyto- and hormone.]
Any substance which has a hormonal effect on a plant; = hormone 2.
| 1933 Chem. Abstr. XXVII. 1645 (heading) Vegetable growth substances... A phytohormone of cell extension. 1940 W. R Fearon Introd. Biochem. (ed. 2) xxiv. 446 The effect of the phytohormones is non-specific as regards species. 1952 [see hormone 2]. 1959 L. J. Audus Plant Growth Substances (ed. 2) i. 16 In the past a rigid distinction has been made between..‘synthetic growth-regulating substances’ and ‘natural phytohormones’. 1971 Nature 4 June 332/1 Jump suggested that a phytohormone produced by A[ureobasidium] pullulans (Dematium pullulans) may have been responsible for forking in red pine. |