Influence of Indole Acetic, Indole Butyric, and Naphthalene Acetic Acids on Roots of Lupinus Albus Seedlings

Plant Growth-Substances. Their chemistry and applications, with special reference to synthetics

“…This contention has received support from the work of Macht and Grumbein (1937) who have considered the question of toxicity of indole-acetic and indole-butyric acids and a naphthalene-acetic acid, from the point of view of the so-called diphasic biological effect familiar to toxicologists and pharmacologists. Their work is discussed in more detail below.…”

Studies on the Phytostatic Action of 2:4‐dichlorophenoxyacetic Acid and Coumarin

“…Thus, the same small external concentration of heteroauxin can bring about a large stimulation of the longitudinal growth of such an organ as an oat coleoptile and yet inhibit almost completely the longitudinal growth of the root. It has been suggested that this inhibition is a case of supra-optimal action (Boysen-Jensen, 1936), since many workers on both excised and intact roots claim to have shown that low concentrations of auxins of the order of i part in io^" bring about an actual stimulation of growth in length of roots (Amlong, 1936;Fiedler, 1936;Thimann, 1936;Geiger-lluber & Burlet, 1936;Grace, 1937;Macht & Grumbein, 1937;Weiler, 1938;Borgstrom, 19396). Implicit however in the term 'hormones', as applied to these substances, is the concept of control of the degree and nature of growth, as we see it exemplified in the vast majority of phenomena associated with auxin action (viz.…”

Growth of Etiolated Sections of Pea Internode Following Exposures to Indole-3-Acetic Acid, 2,4-Dichlorophenoxyacetic Acid and 2,5-Dichlorobenzoic Acid.

“…However, when these chemicals are applied to whole plants, only one dose of the growth regulator is usually given and it is the growth response subsequent to this application which is studied. Comparable studies in short-term laboratory tests have received scant attention, although some investigations have been carried out with roots (8,12). Apart from experiments with supraoptimal concentra-tions on Avena coleoptile sections (9) little is known about the growth responses of excised sections of stem tissue following a single brief period of exposure to growth substances.…”