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powdery mildew
noun
1
: an ascomycetous fungus (family Erysiphaceae) producing abundant powdery conidia on the host
2
: a plant disease caused by a powdery mildew
Examples of powdery mildew in a Sentence
Recent Examples on the Web
What’s more, airflow is restricted when plants are sown too closely together and this can cause plant diseases, like powdery mildew, to spread.
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Lauren Landers, Better Homes & Gardens, 12 Feb. 2025
Excess water on leaves causes powdery mildew. Deadheading, or pinching off the dead flower heads, encourages more blooms, extends the flowering season and improves the plants’ appearance.
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Clarence Schmidt, San Diego Union-Tribune, 14 Jan. 2025
Several fungal diseases, including tar spot, leaf spot, and powdery mildew, can impact holly foliage.
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Kim Toscano, Southern Living, 11 Dec. 2024
Mountain ash is also susceptible to few fungal diseases such as apple scab, cedar-quince rust, and powdery mildew.
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Rita Pelczar, Better Homes & Gardens, 20 Nov. 2024
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Word History
First Known Use
1889, in the meaning defined at sense 1
Dictionary Entries Near powdery mildew
Cite this Entry
“Powdery mildew.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/powdery%20mildew. Accessed 19 Feb. 2025.
Kids Definition
powdery mildew
noun
: a fungus that is a parasite and produces a large number of powdery spores on the host
also
: a plant disease caused by such a fungus
More from Merriam-Webster on powdery mildew
Britannica.com: Encyclopedia article about powdery mildew
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