Chrysanthemum White Rust vs coast amaranth

Puccinia horiana compared with Amaranthus pumilus

Key Differences

• Chrysanthemum White Rust is Not Evaluated while coast amaranth is Extinct.

Taxonomic Classification

Rank	Chrysanthemum White Rust	coast amaranth
Kingdom	Fungi (Fungi)	Plantae (Plants)
Phylum	Basidiomycota (Club Fungi)	Magnoliophyta (Flowering Plants)
Class	Pucciniomycetes (Pucciniomycetes)	Magnoliopsida (Dicots)
Order	Pucciniales (Pucciniales)	Caryophyllales (Caryophyllales)
Family	Pucciniaceae	Amaranthaceae
Genus	Puccinia	Amaranthus
Species	Puccinia horiana	Amaranthus pumilus

Conservation Status

Chrysanthemum White Rust

NE — Not Evaluated

coast amaranth

EX — Extinct

Physical Characteristics

Attribute	Chrysanthemum White Rust	coast amaranth
Diet	—	—
Average Lifespan	—	—
Average Length	—	—
Average Weight	—	—

Habitat & Geographic Range

Chrysanthemum White Rust

Habitat

Native to Asia and Europe and South America, inhabiting ecosystems characteristic of the region.

Range

Widely distributed across Asia (Taiwan), Europe (12 countries), and South America (Brazil).

coast amaranth

Habitat

Typically found in diverse terrestrial habitats from tropical forests to temperate regions.

Range

Found in Japan.

Chrysanthemum White Rust

Chrysanthemum white rust is a disease caused by the fungal pathogen Puccinia horiana, a biotrophic rust fungus in the family Pucciniaceae. It is one of the most serious diseases affecting cultivated chrysanthemums globally and is classified as a quarantine pathogen in many countries. The disease was first described in Japan in the early twentieth century and has since spread to major chrysanthemum-producing regions worldwide through the international movement of infected plant material. Symptoms include pale green to yellow spots on the upper leaf surface corresponding to circular to angular white to pale pink pustules on the underside of the leaf, which produce masses of waxy, white teliospores. Unlike many rust fungi, Puccinia horiana has a simplified life cycle that does not require an alternate host, completing its development entirely on chrysanthemum. The fungus spreads readily via windborne spores, water splash, and contaminated cutting tools. Under cool, humid conditions with high relative humidity, infection can progress rapidly, causing extensive leaf damage and defoliation in severely affected plants. Strict phytosanitary measures including inspection of imported planting material, sanitation of growing facilities, and fungicide application are employed to manage the disease in commercial chrysanthemum production.

coast amaranth

Coast amaranth (Amaranthus pumilus) is an annual herb in the family Amaranthaceae, native to the Atlantic and Gulf coasts of the eastern United States, where it once grew on coastal foredunes, beach strand, and shell-hash substrates above the high tide line from New York south to South Carolina. It is a low-growing, fleshy plant with small, rounded leaves and inconspicuous green flowers typical of the genus. Coast amaranth is assessed as Extinct in the Wild by the IUCN, as it has not been reliably documented from wild populations since the mid-20th century; the last confirmed collections date to the 1960s. The species' decline and likely extinction resulted from intense human pressure on Atlantic coastal habitats through shoreline development, beach stabilisation, vehicular traffic on beaches, and increased storm frequency disrupting pioneer dune vegetation. It is federally listed as Threatened in the United States, though this listing predates confirmed extinction in the wild. A small number of ex-situ accessions may exist in botanical garden collections. Genetic material and seed banking efforts represent the only remaining conservation options for this critically reduced species.