St. Paul, Minn. (October 4, 2005)—A number of plant diseases may be haunting the pumpkin patch this Halloween. While plant diseases don’t pose a health risk to humans, plant diseases do affect a pumpkin’s quality, from appearance to taste.
“The plant disease that is having the biggest impact on this year’s pumpkin crops is downy mildew,” said Daniel S. Egel, extension plant pathologist at the Southwest Purdue Agricultural Center, Vincennes, IN. “Downy mildew affects the foliage of the plant and, while it doesn’t directly hurt the fruit, it can affect the overall quality of the pumpkin,” Egel said. Pumpkins with downy mildew may be smaller in size and may be lower in quality. For example, because downy mildew causes the plant to lose its leaves, infected pumpkins may have areas that are sunken due to exposure to the sun.
Another disease that affects pumpkins is Phytophthora blight. This disease is usually found in regions that have experienced heavy rainfall. Pumpkins with Phytophthora blight will have areas of white mold that appears fuzzy. Another disease, bacterial fruit spot, will cause scabby lesions to appear on the fruit.
Plant doctors with The American Phytopathological Society (APS) suggest the following tips to help you select a healthy Halloween pumpkin:
- Visually check for moldy areas or soft spots on the fruit (remember to check the bottom).
- Check the stem; healthy stems are green in color. A good stem will support the weight of the fruit.
- Most pumpkin varieties are a bright orange when mature. A yellow pumpkin may not be completely mature.
- If possible, keep your pumpkin in a dry, shady place and try to prevent it from freezing. This should increase the ‘porch life’ of your pumpkin.
- Once pumpkins are carved, the process of decay will become more rapid. To help insure that a Jack-o-Lantern lasts through Halloween, don’t carve it until a few days before the event.
The American Phytopathological Society (APS) is a nonprofit, professional scientific organization. The research of the organization’s 5,000 worldwide members advances the understanding of the science of plant pathology and its application to plant health.