DISEASE: Angular leaf spot
HOST: Strawberry
Early stage of disease begins as water-soaked, angular lesions, often with yellow ooze. There also are blight and vascular collapse stages.
Angular leaf spot | Strawberry
DISEASE: Angular leaf spot
HOST: Strawberry (Fragaria × ananassa)
PATHOGEN: Xanthomonas fragariae
SOURCE: M. Schroth
DISEASE: Angular leaf spot
HOST: Strawberry
Advanced stage of disease with dry, brownish necrotic lesions on upper leaf surface.
Angular leaf spot | Strawberry
DISEASE: Angular leaf spot
HOST: Strawberry (Fragaria chiloensis)
PATHOGEN: Xanthomonas fragariae
SOURCE: A. Alvarez
DISEASE: Angular leaf spot
HOST: Strawberry
Diseased sepals.
Angular leaf spot | Strawberry
DISEASE: Angular leaf spot
HOST: Strawberry (Fragaria × ananassa)
PATHOGEN: Xanthomonas fragariae
SOURCE: M. Schroth
DISEASE: Angular leaf spot
HOST: Strawberry
Vascular collapse stage occurs from systemic invasion of crown region.
Angular leaf spot | Strawberry
DISEASE: Angular leaf spot
HOST: Strawberry (Fragaria × ananassa)
PATHOGEN: Xanthomonas fragariae
SOURCE: M. Schroth
DISEASE: Corn stunt
HOST: Corn (Maize)
Chlorosis of leaf margins, the first symptom of disease.
Corn stunt | Corn (Maize)
DISEASE: Corn stunt
HOST: Corn (Maize) (Zea mays)
PATHOGEN: Spiroplasma kunkelii
SOURCE: T. Tsai, M. Davis
DISEASE: Elm yellows
HOST: Elm
Symptoms of elm yellows occasionally appear on one branch before others, but more often they involve the entire crown.
Elm yellows | Elm
DISEASE: Elm yellows
HOST: Elm (Ulmus americana)
PATHOGEN: 'Candidatus Phytoplasma ulmi'
PATHOGEN SYNONYM: Phytoplasma Elm yellows group
SOURCE: W. Sinclair
DISEASE: Elm yellows
HOST: Elm
Diseased twig (right) with epinasty, chlorosis, and yellowing of leaves. Sometimes both yellow and green leaves occur on same branch. Healthy branch (left).
Elm yellows | Elm
DISEASE: Elm yellows
HOST: Elm (Ulmus americana)
PATHOGEN: 'Candidatus Phytoplasma ulmi'
PATHOGEN SYNONYM: Phytoplasma Elm yellows group
SOURCE: W. Sinclair
DISEASE: Elm yellows
HOST: Elm
Branches with butterscotch discoloration (center) and necrotic flecks in phloem and vascular cambium (right). Healthy branch (left). Sudden wilt and browning is common with small trees.
Elm yellows | Elm
DISEASE: Elm yellows
HOST: Elm (Ulmus americana)
PATHOGEN: 'Candidatus Phytoplasma ulmi'
PATHOGEN SYNONYM: Phytoplasma Elm yellows group
SOURCE: W. Sinclair
DISEASE: Elm yellows
HOST: Elm
Elm yellows is characterized by witches'-brooms and stunting. Some cultivars have both yellow and reddish foliar discoloration.
Elm yellows | Elm
DISEASE: Elm yellows
HOST: Elm (Ulmus parvifolia)
PATHOGEN: 'Candidatus Phytoplasma ulmi'
PATHOGEN SYNONYM: Phytoplasma Elm yellows group
SOURCE: W. Sinclair