Pyrabactin is a synthetic sulfonamide that mimics abscisic acid (ABA), a naturally produced stress hormone in plants that helps them cope with drought conditions by inhibiting growth. ABA can be manufactured for agricultural use; however, ABA is light-sensitive and costly to make. Pyrabactin is relatively inexpensive, easy to make, and not sensitive to light. Unlike ABA, pyrabactin activates only a few of the 14 ABA receptors in the plant needed for effective drought tolerance.[1] Its role as an ABA mimic may make pyrabactin an important tool for protecting crops against drought and cold weather.[2] [3]
The discovery of pyrabactin by Sean Cutler was named a breakthrough research of 2009 by Science magazine.[4]
Pyrabactin (for pyridyl containing ABA activator) is a naphthalene sulfonamide hypocotyl cell expansion inhibitor. A combination of genetic, transcriptomic and physiological evidence demonstrated that pyrabactin activates the ABA pathway in a manner very similar to ABA.[5] As such, pyrabactin is the first ABA agonist that is not an ABA analog and may ultimately lead to the development of a new family of synthetic plant growth regulators.