Identification of colletotrichum species responsible for anthracnose and root necrosis of strawberry in Israel.

TLDR: Using morphological and cultural characteristics, the species responsible for anthracnose was identified as Colletotrichum acutatum and a reliable semi-selective medium, amended with iprodione and lactic acid, was used to isolate the fungus from infected tissues.

Abstract: Strawberry anthracnose was observed for the first time in Israel in 1995. The disease reached epidemic proportions in Israeli nurseries and production fields in 1995 and 1996. Using morphological and cultural characteristics, the species responsible for anthracnose was identified as Colletotrichum acutatum. A reliable semi-selective medium, amended with iprodione and lactic acid, was used to isolate the fungus from infected tissues. In addition, C. acutatum was subsequently isolated from necrotic roots of stunted, chlorotic plants that exhibited no symptoms of anthracnose. High levels of the pathogen from naturally infested field soil and perlite growth substrate were quantified from the rhizosphere of diseased plants on the iprodione-amended medium. Both foliar- and rootinfecting isolates were equally pathogenic to strawberry, causing 95 to 100% plant mortality, when inoculated on roots and foliage. In complementation (heterokaryon) tests using nitrate nonutilizing mutants, 113 out of 115 isolat...