Auxins are a class of plant growth substance and morphogens. Auxins have an essential role in coordination of many growth and behavioral processes in the plant life cycle. Auxins and their role in plant growth were first revealed by the Dutch scientist Frits Went..
2,4-Dichlorophenoxyacetic acid (2,4-D) is a common systemic 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 also an important synthetic auxin, often used in laboratories for plant research and as a supplement in plant cell culture media such as MS medium.
Indole-3-acetic acid, also known as IAA, is a heterocyclic compound that is an phytohormone called auxins. This colourless solid is probably the most important plant auxin. The molecule is derived from indole, containing a carboxymethyl group (acetic acid).
Phenylacetic acid is an organic compound containing a phenyl functional group and an acetic acid functional group. It is a white solid with a disagreeable odor. Because it is used in the illicit production of phenylacetone, it is subject to controls in the United States.
Indole-3-butyric acid (1H-Indole-3-butanoic acid, IBA) is a white to light-yellow crystalline solid, with the molecular formula C12H13NO2. It melts at 125 °C in atmospheric pressure and decomposes before boiling.
1-Naphthaleneacetic acid, commonly abbreviated NAA, is an organic compound with the formula C10H7CH2CO2H. This colourless solid is soluble in organic solvents. It features a carboxylmethyl group (CH2CO2H) linked to the "1-position" of naphthalene. NAA is a plant hormone in the auxin family and is an ingredient in many commercial plant rooting horticultural products; it is a rooting agent and used for the vegetative propagation of plants from stem and leaf cutting.
2,4,5-Trichlorophenoxyacetic acid (2,4,5-T), a synthetic auxin, is a chlorophenoxy acetic acid herbicide used to defoliate broad-leafed plants. It was developed in the late 1940s and was widely used in the agricultural industry until being phased out, starting in the late 1970s due to toxicity concerns. Agent Orange, a defoliant used by the U.S. in the Vietnam War, was equal parts 2,4,5-T and 2,4-D.
Dichlorprop is a chlorophenoxy herbicide similar in structure to 2,4-D that is used to kill annual and perennial broadleaf weeds. It is a component of many common weedkillers. About 4 million pounds of dichlorprop are used annually in the United States.
4-Chloroindole-3-acetic acid (4-Cl-IAA) is a natural plant hormone. It is a member of the class of compounds known as auxins and a chlorinated derivative of the more common auxin indole-3-acetic acid (IAA). 4-Cl-IAA is found in the seeds of a variety of plants, particularly legumes such as peas and broad beans. It is hypothosized that 4-Cl-IAA may be a "death hormone" that maturing seeds use to trigger death of the parent plant by mobilizing nutrients to be stored in the seed.