Tom Creswell, P&PDL Director and Plant Disease
Anthurium is a relatively
easy to grow tropical plant for the house, however, you may encounter
an occasional disease problem. This Anthurium sample has Cercospora
leaf spot. The spots start as small discolored areas, increasing
to large tan to brown irregular blotches. Close examination with
a hand lens shows a olive drab to black areas of “fuzziness” in
the lesions where spores are produced under humid conditions. This
disease may be difficult to control but removing all dead and spotted
leaves and any debris from the pot surface can help. Make sure
the plant receives proper water and nutrition and that leaves don’t
get wet when watering.
Click image to enlarge
Photo 1: Upper and lower leaf surfaces showing Cercospora leaf spots
of various ages and sizes.
Photo 2: Closer view of an individual spot showing the tan to brown
discoloration. Note the fuzzy area at the top of the lesion where
spores are being produced.
Photo 3: Close up of a spot with sporulation.
Photo 4: Microscopic view of spores.