Photo 1. Marginal rot of cucumber leaf caused by gummy stem blight, Didymella bryoniae, more advanced than in Photo 1.
Photo 2. Marginal rot with yellow margin caused by gummy stem blight, Didymella bryoniae, on cucumber.
Cucumner gummy stem blight, cucubit gummy stem blight, gummy stem blight of cucurbits. See also Watermelon gummy stem blight (Fact Sheet no. 07).
Stagonosporopsis cucurbitacearum; (previously, Didymella bryoniae). Also known by the asexual state, Phoma cucurbitacearum or Ascochyta cucumis. The later is commonly found on plants in the field producing minute oval spores in round black structures in the leaf called "pycnidia" that are just visible to the naked eye.
AUTHORS Grahame Jackson
Photos 2 Gerald Holmes, California Polytechnic State University at San Luis Obispo, Bugwood.org.
Produced with support from the Australian Centre for International Agricultural Research under project PC/2010/090: Strengthening integrated crop management research in the Pacific Islands in support of sustainable intensification of high-value crop production, implemented by the University of Queensland and the Secretariat of the Pacific Community.
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