downy mildew


Definition of downy mildew

1 : any of various parasitic lower fungi (family Peronosporaceae) that produce whitish masses of sporangiophores or conidiophores on the undersurface of the leaves of the host
2 : a plant disease caused by a downy mildew

Examples of downy mildew in a Sentence

Recent Examples on the Web Basil downy mildew flourishes in warm, humid environments. Tim Johnson,, "Yellowing basil leaves could mean downy mildew," 26 Aug. 2019 Basil downy mildew affects homeowners with a few basil plants, as well as large-scale commercial growers. Tim Johnson,, "Yellowing basil leaves could mean downy mildew," 26 Aug. 2019 The problem with your basil plants is most likely a disease called downy mildew. Tim Johnson,, "Yellowing basil leaves could mean downy mildew," 26 Aug. 2019 Hops are unhappy in Washington, suffering from the heat, downy mildew and Japanese beetles, to name a few issues. Washington Post, "Vines are a romantic addition to the garden — until they go rogue," 9 July 2019 Repeat applications of natural horticultural oils or soaps can normally control the mites and thrips but preventing downy mildew is going to take a fungicide. Tom Maccubbin,, "Consistent care, pest control make keeping poinsettias manageable," 23 Dec. 2017 But the problem of downy mildew, which damaged the leaves and vines of the plant, wasn’t such a simple solve. Kat Eschner, Smithsonian, "How One Mycologist Saved France’s Wine (Among Other Things)," 13 Dec. 2017

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'downy mildew.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of downy mildew

1886, in the meaning defined at sense 1

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The first known use of downy mildew was in 1886

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Cite this Entry

“Downy mildew.” Dictionary, Merriam-Webster, Accessed 26 Nov. 2020.

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