Shot-hole Disease of Stone Fruits caused by Clasterosporium carpophilum

Abstract

PURE cultures of the fungus Clasterosporium carpophilum were isolated from recent infections of peach leaves and fruits. Isolation trials showed that the fungus is viable in leaf lesions from March until September. For this purpose, infected parts were washed thoroughly in sterile water and small portions of the diseased tissues were placed on corn-meal agar at 25° C. Hyphal tips were taken from the edge of the growing colonies and these were left to grow on corn-meal slants. In some cases, infected portions were sterilized using, first, 1 per cent silver nitrate solution for two minutes and then sodium chloride for 3–4 minutes and then washing thoroughly in sterile water.