(hormone): Substances of growth were produced by certain plant cells, mostly transported out of the place of synthesis. They act in tiny doses and regulate certain physiological processes. The main hormones being auxins, cytokinins, gibberellins, the abscissic acid and the ethylene.
(botany) a hormone-like plant product
These are products registered as pesticides that do not control pests but change the shape or appearance of the plant, stop or start plant growth, prevent flowering and other functions.
Synthetic or naturally occurring plant substances that are effective in minute amounts to regulate or modify plant growth.
A natural or chemical substance that regulates the enlargement, division or activation of plant cells
A substance used for controlling or modifying plant growth processes.
The term given to a group of chemicals, principally synthetic plant hormones, which modify the natural growth of (mainly) cereals, particularly winter wheat and winter barley, as an aid to optimising agricultural profitability.