Erwiniaceae

Erwiniaceae is a bacterial family proposed for certain members of the order Enterobacterales, within the class Gammaproteobacteria. The name derives from the genus Erwinia, long associated with plant-pathogenic bacteria. In different taxonomic frameworks, the circumscription of Erwiniaceae has varied: some classifications historically grouped Erwinia and closely related genera in a single family named Erwiniaceae, while others place these taxa within Enterobacteriaceae or recognize a separate family such as Erwiniaceae. Because taxonomic opinions differ, not all databases agree on membership of this family.

Organisms attributed to Erwiniaceae are typically Gram-negative, rod-shaped, non-spore-forming, and facultatively anaerobic. They are primarily associated with plant environments and are often heterotrophic. The group is notable for including pathogenic species that affect crops and ornamental plants.

Ecology and pathogenicity within the proposed group are best known for plant-disease relevance. Erwinia amylovora, for example, is the etiological agent of fire blight in apples and pears, a widely studied plant disease. Related taxa have been implicated in soft rot and wilt diseases of various plant hosts, attributed to enzymatic degradation of plant cell walls and tissue maceration.

Taxonomic note: modern bacterial classification continues to evolve, and different authorities (such as LPSN, NCBI taxonomy, and Bergey’s Manual) may place the included genera in different higher-level taxa. As a result, Erwiniaceae may be recognized in some schemes and not in others.

See also: Erwiniaceae, Enterobacterales, plant pathology, fire blight.