DISEASE: Aster yellows
HOST: Marigold
Infected plant (left) with yellowing and stunting.
Aster yellows | Marigold
DISEASE: Aster yellows
HOST: Marigold (Tagetes erecta)
PATHOGEN: 'Candidatus Phytoplasma asteris'
PATHOGEN SYNONYM: Phytoplasma Aster yellows group
SOURCE: M. Shurtleff
DISEASE: Fire blight
HOST: Scarlet firethorn
Pyracantha with blighted twig. Ingress was probably through blossoms. Cankers commonly occur on branches.
Fire blight | Scarlet firethorn
DISEASE: Fire blight
HOST: Scarlet firethorn (Pyracantha coccinea)
PATHOGEN: Erwinia amylovora
SOURCE: W. Sinclair
DISEASE: Phytoplasma disease
HOST: Gayfeather
Gayfeather with phyllody of flowers.
Phytoplasma disease | Gayfeather
DISEASE: Phytoplasma disease
HOST: Gayfeather (Liatris sp.)
PATHOGEN: 'Candidatus Phytoplasma asteris'
PATHOGEN SYNONYM: Phytoplasma Aster yellows group
SOURCE: R. Raabe
DISEASE: Pseudomonas leaf spot
HOST: Marigold
Marigolds with yellow apical chlorosis attributed to toxin production by the pathogen.
Pseudomonas leaf spot | Marigold
DISEASE: Pseudomonas leaf spot
HOST: Marigold (Tagetes erecta)
PATHOGEN: Pseudomonas syringae pv. tagetis
SOURCE: R. Durbin
DISEASE: Pseudomonas leaf spot
HOST: Marigold
Chlorotic leaves with total loss of chlorophyll. Disease is also known as toxic chlorosis.
Pseudomonas leaf spot | Marigold
DISEASE: Pseudomonas leaf spot
HOST: Marigold (Tagetes erecta)
PATHOGEN: Pseudomonas syringae pv. tagetis
SOURCE: R. Durbin