Fungal crown rot of
Soft rot of several species of Echinocereusis
caused by a species of
Helminthosporium, a fungal pathogen that
produces airborne spores
abundantly. These spores are easily
disseminated in splashing water and windborne rain.
The first symptom of infection is dark, sunken
areas that are soft and water soaked In Echinocereus, disease may begin
anywhere on the upper part of the cactus and causes an internal soft rot .In
pad cacti, sunken soft-rotted areas appear on the pad surface.
Water management is probably important for
prevention of this disease, but to date no research has been done to determine
the optimum conditions for disease development.
Applications of fungicides such as
thiophanate-methyl may help prevent infection where disease has been
problematic. Infected plants should be removed so that they are not sources of
spores that will infect nearby plants.