thidiauron

Thidiauron, also known as thidiazuron (TDZ), is a synthetic plant growth regulator with strong cytokinin-like activity. It is a member of the phenylurea class of compounds and is primarily used in plant tissue culture rather than as a field spray. In plant tissue culture, thidiauron acts as a powerful inducer of shoot organogenesis and somatic embryogenesis across a broad range of species.

In vitro applications rely on thidiauron’s ability to promote cytokinin-like responses, often at low micromolar concentrations. It can replace or supplement traditional cytokinins such as benzylaminopurine (BAP) and is commonly used in combination with auxins to direct the balance between shoot formation and callus development. Depending on the species and explant, TDZ can trigger direct shoot organogenesis, induce shoot primordia on callus, or stimulate somatic embryos.

Mechanistically, thidiauron modulates cytokinin signaling pathways, though its exact mode of action can vary by species. It is not a natural plant hormone, but its effects resemble those of cytokinins, leading to enhanced cell division and shoot initiation in tissue culture settings.

Safety and regulatory considerations: thidiauron is handled as a laboratory or manufacturing chemical in tissue culture settings. It is not typically registered as a general-use agricultural pesticide for field application, and local regulations govern its handling, usage, and disposal.

See also: cytokinins, plant tissue culture, somatic embryogenesis, plant growth regulators.