Cylindrocladium Root Rot, Leaf Spot and Stem Canker --
Cylindrocladium spp. Host: Azalea, heliconia, rose, and
spathiphyllum Symptoms: Yellowing of lower leaves and wilting
are indications of root rot. Cylindrocladium stem cankers cause
a brown, internal discoloration of the stem of azalea. The
vascular browning extends to approximately 1 inch above the soil
line. Angular leaf spots, bounded by leaf veins, are caused by
Cylindrocladium on azalea. Defoliation may occur. Root and
petiole rot are common on spathiphyllum. Conditions Favoring
Disease: The disease on azaleas occurs only in greenhouses and
is favored by high humidity and temperatures of approximately
85°F. How Pathogen Survives/Disperses: The conidia are easily
carried on hands and by wind and water. Water-dispersed conidia
from fallen infected leaves can also wash into the soil where
they can cause root rot. Microsclerotia survive in soil for
years. Photo and write up provided by Syngenta Professional
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