Pacific Pests, Pathogens, Weeds & Pesticides - Online edition

Pacific Pests, Pathogens, Weeds & Pesticides

Cucumber gummy stem blight (201)


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Summary

  • Worldwide distribution. On watermelon and other cucurbits. An important disease causing a leaf blight.
  • Spots on leaves grow rapidly, leaves blacken shrivel and die. Spots on vine leak a gummy (sticky) liquid.
  • Spores from black sacs in the spots spread in wind and rain. For cucumber (see Fact Sheet no. 201).
  • Cultural control: nursery far from production area; sterilise soil; check seedlings before planting; do not plant new crops next to old; 3-year crop rotations; collect and burn trash after harvest.
  • Chemical control: copper, mancozeb, or chlorothalonil every 7-10 days.

Common Name

Cucumber gummy stem blight, cucurbit gummy stem blight, gummy stem blight of cucurbits. See also Watermelon gummy stem blight (Fact Sheet no. 07).

Scientific Name

Stagonosporopsis cucurbitacearum; (previously, Didymella bryoniae). Also known by the asexual state, Phoma cucurbitacearum or Ascochyta cucumis. The latter 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.


AUTHOR Grahame Jackson
Information from CABI (2019) Didymella bryoniae (gummy stem blight of cucurbits). Invasive Species Compendium. (https://www.cabi.org/isc/datasheet/18900); and from DAF (2016) Gummy stem blight. Queensland Government. (https://www.daf.qld.gov.au/business-priorities/agriculture/plants/fruit-vegetable/diseases-disorders/gummy-stem-blight). Photo 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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