The silver-leaf pathogen, Stereum purpureum (Pers.) Fr.: studies on its toxins and nutriton

Abstract

A brief introduction to the etiology of the silver-leave disease caused by Stereum purpureum is given. The present study has been concerned with the nutrition of the pathogen and the toxins which it produces. Three toxins produced by the fungus while growing in pure culture, were detected. (a) Silvering Toxin. The toxin responsible for the leaf silvering symptom observed in the field was detected in xylem sap collected from peach trees naturally infected with S. purpureum, and in culture filtrates following growth of the fungus both in xylem sap from a healthy peach trees and in synthetic media. The presence of the toxin was demonstrated by uptake into healthy peach seedlings after filter sterilization of the test solutions.