Definition

Noun A species of fungus belonging to the genus Peronospora. It is an oomycete pathogen that causes a specific downy mildew disease, primarily affecting tobacco plants (Nicotiana tabacum) during their growth phase.

Usage

The term is used in scientific, agricultural, and botanical contexts to specifically identify the causal agent of tobacco downy mildew. * The crop failure was attributed to an infection by Peronospora hyoscyami. * Researchers are studying the life cycle of Peronospora hyoscyami to develop resistant tobacco varieties.

Advanced Usage

• The name follows binomial nomenclature, where is the genus and is the specific epithet. It is often italicized in academic writing.
• While its primary host is tobacco, related species cause downy mildews on a wide range of plants.

Variants and Related Words

• Downy mildew (n): The common name for the type of plant disease caused by oomycetes like , characterized by fuzzy, down-like growth on the undersides of leaves.
• Oomycete (n): A classification of fungus-like microorganisms, also known as water molds, to which belongs.
• Pathogen (n): An organism that causes disease.

Synonyms

• Tobacco downy mildew pathogen (descriptive synonym)

Notes on Meaning

This is a highly specific taxonomic term. It does not have general or figurative meanings. It refers exclusively to this biological entity.

Noun

1. fungus causing a downy mildew on growing tobacco