Gray Mold (5708)

The plant pathogenic fungus Botrytis is found virtually everywhere plants are grown. It is fast growing, can grow on many different sources of nutrients, survives well in the greenhouse, and can attack many different types of plants. The disease caused by Botrytis is commonly called Botrytis blight or gray mold.

The Fungus
Botrytis at first appears as a white growth on the plant but very soon darkens to a gray color. Smoky-gray "dusty" spores form and are spread by the wind or in water. In greenhouses, any activity will result in a release of spores. Even automated trickle irrigation systems, when turned on, trigger a release of spores. These spores are often found on the outside of seeds. The spores can remain dormant on plant surfaces as long as the life of the plant in some cases. Botrytis forms two types of resting structures on or in infected plant tissue: (1) very dark-brown or black multicelled structures called sclerotia and (2) single-celled, thick, dark-walled chlamydospores. The fungus can persist in the greenhouse for long periods in either structure in the absence of plants.

For more information, please see this Penn State Fact Sheet

Penn State Horticulture Department

Penn State Plant Pathology Department

For more information on this subject, Please visit the College of Agricultural Sciences Publications Web site.

Feel free to forward, post or reprint any of the "Solutions" in their entirely, but please credit http://www.solutions.psu.edu/ as the original source of information, and please do not change the content.