DISEASE: Ash yellows
HOST: Ash
Ash sapling with basal sprouts and chlorotic leaves.
Ash yellows | Ash
DISEASE: Ash yellows
HOST: Ash (Fraxinus pennsylvanica)
PATHOGEN: 'Candidatus Phytoplasma fraxini'
PATHOGEN SYNONYM: Phytoplasma Ash yellows group
SOURCE: W. Sinclair
DISEASE: Ash yellows
HOST: Ash
Witches'-broom at base of declining tree.
Ash yellows | Ash
DISEASE: Ash yellows
HOST: Ash (Fraxinus velutina)
PATHOGEN: 'Candidatus Phytoplasma fraxini'
PATHOGEN SYNONYM: Phytoplasma Ash yellows group
SOURCE: W. Sinclair
DISEASE: Ash yellows
HOST: Ash
Forest of declining trees, some chlorotic and others with dieback.
Ash yellows | Ash
DISEASE: Ash yellows
HOST: Ash (Fraxinus americana)
PATHOGEN: 'Candidatus Phytoplasma fraxini'
PATHOGEN SYNONYM: Phytoplasma Ash yellows group
SOURCE: W. Sinclair
DISEASE: Ash yellows
HOST: Ash
White ash with deliquescent branching.
Ash yellows | Ash
DISEASE: Ash yellows
HOST: Ash (Fraxinus americana)
PATHOGEN: 'Candidatus Phytoplasma fraxini'
PATHOGEN SYNONYM: Phytoplasma Ash yellows group
SOURCE: W. Sinclair
DISEASE: Bacterial decline
HOST: Papaya
Bacterial decline of papaya, historically called St. Croix decline, was thought to be caused by a fungus. This picture shows a papaya with dead top and side branches, a severe stage of the disease.
Bacterial decline | Papaya
DISEASE: Bacterial decline
HOST: Papaya (Carica papaya)
PATHOGEN: Erwinia papayae
SOURCE: M. Schroth
DISEASE: Bacterial decline
HOST: Papaya
Water-soaked papaya stem in St. Croix. Dark, water-soaked, greasy lesions occur on stems and leaves. The causal agent differs somewhat from descriptions of Erwinia papayae D strains in Micronesia.
Bacterial decline | Papaya
DISEASE: Bacterial decline
HOST: Papaya (Carica papaya)
PATHOGEN: Erwinia papayae
SOURCE: M. Schroth
DISEASE: Bacterial decline
HOST: Papaya
Bacterial invasion of leaf veins and adjacent tissues of papaya in Micronesia. This disease has also been called canker, dieback, and blight.
Bacterial decline | Papaya
DISEASE: Bacterial decline
HOST: Papaya (Carica papaya)
PATHOGEN: Erwinia papayae
SOURCE: E. Trujillo
DISEASE: Bacterial decline
HOST: Papaya
Complete destruction of papaya plantation in Micronesia. Only a severely damaged trunk remains.
Bacterial decline | Papaya
DISEASE: Bacterial decline
HOST: Papaya (Carica papaya)
PATHOGEN: Erwinia papayae
SOURCE: E. Trujillo
DISEASE: Foamy canker
HOST: Almond
White, macerated tissues near cambium region is characteristic of disease. Foam is usually associated with cankers. The disease is suspected to be bacterial but the causal agent has not been identified.
Foamy canker | Almond
DISEASE: Foamy canker
HOST: Almond (Prunus dulcis)
PATHOGEN: Causal agent unknown
SOURCE: B. Teviotdale