Davies, Peter J. School of Integrative Plant Science, Cornell University, Ithaca, New York.
Last reviewed:April 2019
Show previous versions
- Nature, occurrence, and effects of hormones
- How plant hormones work
- Abscisic acid
- Salicylic acid
- Signal peptides
- Links to Primary Literature
- Additional Readings
Any of a group of naturally occurring, organic substances that influence plant physiological processes at low concentrations. Plant hormones are chemical messengers synthesized within plants, where they help to regulate a variety of physiological processes (Fig. 1). The processes consist mainly of growth, differentiation, and development, although other processes, such as stomatal movement, may also be affected by plant hormones. Typical effective concentrations [in the range of 1 μM externally, or about 1–100 nM internally (about 1 part per billion), depending on the compound] are far below those where either nutrients or vitamins would be effective. See also: Hormone; Plant; Plant anatomy; Plant development; Plant growth; Plant physiology
The content above is only an excerpt.
for your institution. Subscribe
To learn more about subscribing to AccessScience, or to request a no-risk trial of this award-winning scientific reference for your institution, fill in your information and a member of our Sales Team will contact you as soon as possible.
to your librarian. Recommend
Let your librarian know about the award-winning gateway to the most trustworthy and accurate scientific information.
AccessScience provides the most accurate and trustworthy scientific information available.
Recognized as an award-winning gateway to scientific knowledge, AccessScience is an amazing online resource that contains high-quality reference material written specifically for students. Contributors include more than 9000 highly qualified scientists and 43 Nobel Prize winners.
MORE THAN 8700 articles covering all major scientific disciplines and encompassing the McGraw-Hill Encyclopedia of Science & Technology and McGraw-Hill Yearbook of Science & Technology
115,000-PLUS definitions from the McGraw-Hill Dictionary of Scientific and Technical Terms
3000 biographies of notable scientific figures
MORE THAN 19,000 downloadable images and animations illustrating key topics
ENGAGING VIDEOS highlighting the life and work of award-winning scientists
SUGGESTIONS FOR FURTHER STUDY and additional readings to guide students to deeper understanding and research
LINKS TO CITABLE LITERATURE help students expand their knowledge using primary sources of information