Plant Growth Regulators

Plants make plant growth regulators, often called phytohormones, to regulate growth, development, and responses to stimuli. Each of these small organic molecules has pleiotropic effects. The balance between them shifts constantly. Changes in phytohormone levels result in gene activation shifts. In tissue culture the concentration of growth regulators in the medium must be optimized and may change according to the desired result. For example, the synthetic auxin 2,4-D is very often the primary phytohormone to support callus formation and maintenance. Cytokinins promote shoot formation, but need auxins as well to promote mitosis. We offer the naturally occurring hormones as well as potent synthetic substitutes. We also offer antagonists, useful as tools for investigating hormonal mechanisms of action.