dichlorophenoxyacetic acid

2,4-Dichlorophenoxyacetic acid (2,4-D) is a common systemic pesticide/herbicide used in the control of broadleaf weeds.It is the most widely used herbicide in the world, and the third most commonly used in North America.

2,4-D is a synthetic auxin (plant hormone), and as such it is often used in laboratories for plant research and as a supplement in plant cell culture media such as MS medium. It was a major ingredient in Agent Orange.