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.