Pacific Pests, Pathogens & Weeds - Mini Fact Sheet Edition

https://apps.lucidcentral.org/ppp/

Cucurbit anthracnose (200)

Search

Photo 1. Angular brown spots on the leaf of watermelon, caused by the anthracnose fungus, Colletotrichum orbiculare.

Photo 2. Round and oval light brown spots showing "shot-hole" symptom on cucumber, caused by the anthracnose fungus, Colletotrichum orbiculare.

Photo 3. Large spots of cucurbit anthracnose, Colletotrichum orbiculare, on melon, showing the greyish water-soaked spots (lower left), and the brown older spots (top right) that are joining together and developing into an extensive rot.

Photo 4. Sunken spots on cucumber caused by anthracnose, Colletotrichum orbiculare.

Summary

• Widespread distribution. In tropics and sub-tropics. A wet-weather disease, common on cucurbits, i.e., members of the cucumber family, especially, cucumber, melon and watermelon. An important disease.
• Angular dark brown spots on watermelon; brown spots on melon and cucumber with halos, and centres that fall out. Large, brown, round, sunken spots on the fruit, with pink spore masses in wet weather.
• Spread in wind-blown rain; longer distances in seed.
• Cultural control: certified seed; tolerant varieties (cucumber, watermelon); check seedlings in nursery; avoid planting near older infected crops; avoid overhead irrigation, or apply early in the day; avoid entering fields when plants are wet; weed; collect and burn trash after harvests; crop rotation.
• Chemical control: copper, chlorothalonil, or mancozeb.

Common Name

Cucurbit anthracnose

Scientific Name

Colletotrichum orbiculare; sometime known as Colletotrichum lagenarium. Three races are known.

This mini fact sheet is a part of the app Pacific Pests, Pathogens & Weeds

The mobile application is available from the Google Play Store and Apple iTunes.