Prohexadione is a plant growth regulator. It inhibits the gibberellin plant hormone biosynthesis enzyme 3β-hydroxylase when used at concentrations of 0.1, 1, and 10 mM. It reduces the shoot length of peanut plants when applied at 0.5, 1.5, and 4.5 kg hectare. Prohexadione also inhibits jumonji domain-containing 2A (JMJD2A) demethylase when used at a concentration of 1 mM and induces the differentiation of mouse neurospheres into neurons at 1, 1.5, and 2 mM. Formulations containing prohexadione have been used as plant growth regulators in agriculture.