Downy mildew of sweet basil is a destructive disease that was first detected in the United States in 2007. Since that first discovery in south Florida, it has rapidly spread to other parts of the United States and was detected in a Louisiana home garden in spring 2009.
The disease is caused by a fungus-like organism known as Peronospora belbaharii. The pathogen belongs to a group of organisms called Oomycetes, commonly known as water molds.
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The LSU AgCenter and the LSU College of Agriculture