The present invention provides a composition capable of regulating growth of aplant or propagation material thereof comprising as plant growth regulatingactive ingredient a mixture of component (A) and component (B) whereincomponent (A) is Paclobutrazole and component (B) is selected from the groupconsisting of Difenoconazole, Ipconazole, Metconazole, Tebuconazole,Prothioconazole, Cyproconazole, Propiconazole and Epoxiconazole whereincomponent (A) and component (B) are present in said composition in amountswhich produce a synergistic effect. Preferably the composition comprisesPaclobutrazole and Difenoconazole and the composition inhibits growth of theplant upon application thereby increasing yield/quality. The compositions arealsocapable of preventing and/or treating growth and/or infestation ofphytopathogenic fungion a plant or propagation material thereof.