growth substance

views updated May 11 2018

growth substance (phytohormone; plant hormone) Any of a number of organic chemicals that are synthesized by plants and regulate growth and development. They are usually made in a particular region, such as the shoot tip, and transported to other regions, where they take effect. See abscisic acid; auxin; cytokinin; ethylene; gibberellin.

growth substance

views updated May 17 2018

growth substance A naturally occurring compound, other than a nutrient, which promotes, inhibits, or otherwise modifies the growth of a plant.

growth substance

views updated May 29 2018

growth substance A naturally occurring compound, other than a nutrient, that promotes, inhibits, or otherwise modifies the growth of a plant.