Treatment for dutch elm disease

摘要

A preventative treatment for Dutch elm disease is disclosed which provides susceptible elm trees with induced resistance to Dutch elm disease-causing fungi such as Ophiostoma ulmi. The treatment comprises administering to a susceptible elm tree an amount of an elicitor effective to cause a defence reaction in the tree. The defence reaction comprises a cascade of events including accumulation by the tree of mansonones, which are sesquiterpene quinones having antifungal properties. The preferred elicitor for use as a treatment for Dutch elm disease is a novel elicitor isolated from cultures of O. ulmi. The preferred elicitor is non-toxic and heat stable and is shown to be effective for inducing resistance to Dutch elm disease in susceptible elm trees.