|Anthracnose||Circular to oval brown leaf spots have a yellow halo. Spots may become two inches in diameter and contain tiny black fungal fruiting structures.||Colletrotrichum gloeosporioides||Avoid overhead watering.Apply a fungicide to protect healthy plants.|
|Bacterial Leaf Spot||Small gray or dark green leaf spots enlarge and become irregularly shaped, tan, dark brown, or black.||Erwinia carotovora or Erwinia chrysanthemi||Purchase plants free of the disease. Remove infected leaves and water in a manner that keeps the surface of the leaves dry.|
|Wilt||Lower leaves yellow, wilt, and die.||Drought||Maintain even soil moisture.|
|Marginal Leaf Burn||Margins of leaves brown and die.||Over-fertilization||Do no over-fertilize. If no slow-release fertilizer is present, leach the potting medium.|
|Myrothecium Leaf Spot||Large gray-brown, oval leaf spots form at leaf tips or margins. Fungal fruiting structures form in concentric rings within the spots on the underside of the leaf.||Myrothecium roridum||Do not apply excessive amounts of nitrogen fertilizer. Apply a fungicide to protect healthy plants.|
|Nitrogen Deficiency||Plants are yellowed with smaller than normal leaves and short internodes.||Lack of fertilization.||Apply a balanced fertilizer solution.|
|Virus||Leaves have a mosaic of light green where they should be dark green. Plants may be stunted, and leaves deformed. Some cultivars die within a month of infection.||Dasheen mosaic virus||Discard infected plants. Maintain good aphid control. Disinfests tools used on the plants.|
Prepared by Gary W. Moorman, Professor of Plant Pathology
Notice: The user of this information assumes all risks for personal injury or property damage.
Warning! Pesticides are poisonous. Read and follow all directions and safety precautions on labels. Handle carefully and store in original labeled containers out of the reach of children, pets, and livestock. Dispose of empty containers right away, in a safe manner and place. Do not contaminate forage, streams or ponds.
Issued in furtherance of Cooperative Extension work, Acts of Congress, May 8 and June 30, 1914, in cooperation with the U. S. Department of Penn State College of Agricultural Sciences research and extension programs are funded in part by Pennsylvania counties, the Commonwealth of Pennsylvania, and the U.S. Department of Agriculture.
Visit Penn State Extension on the web at extension.psu.edu.
Where trade names appear, no discrimination is intended, and no endorsement by Penn State Cooperative Extension is implied.
This publication is available in alternative media on request.
The Pennsylvania State University is committed to the policy that all persons shall have equal access to programs, facilities, admission, and employment without regard to personal characteristics not related to ability, performance, or qualifications as determined by University policy or by state or federal authorities. It is the policy of the University to maintain an academic and work environment free of discrimination, including harassment. The Pennsylvania State University prohibits discrimination and harassment against any person because of age, ancestry, color, disability or handicap, national origin, race, religious creed, sex, sexual orientation, gender identity, or veteran status. Discrimination or harassment against faculty, staff, or students will not be tolerated at The Pennsylvania State University. Direct all inquiries regarding the nondiscrimination policy to the Affirmative Action Director, The Pennsylvania State University, 328 Boucke Building, University Park, PA 16802-5901; Tel 814-865-4700/V, 814-863-1150/TTY.