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: Aster yellows
HOST: Onion
Infected plants with yellowish, malformed leaves.
Aster yellows | Onion
DISEASE: Aster yellows
HOST: Onion (Allium cepa)
PATHOGEN: 'Candidatus Phytoplasma asteris'
PATHOGEN SYNONYM: Phytoplasma Aster yellows group
SOURCE: R. Rowe
DISEASE: Aster yellows
HOST: Onion
Onion flower with unusual symptoms (left) compared with healthy inflorescence (right). Flowers are distorted and often have abnormally long pedicels. Young leaves may have yellow streaks or a general yellowing of basal portions.
Aster yellows | Onion
DISEASE: Aster yellows
HOST: Onion (Allium cepa)
PATHOGEN: 'Candidatus Phytoplasma asteris'
PATHOGEN SYNONYM: Phytoplasma Aster yellows group
SOURCE: R. Raabe
DISEASE: Bacterial blight
HOST: Geranium
Leaf with many necrotic spots and chlorotic V-shaped lesions.
Bacterial blight | Geranium
DISEASE: Bacterial blight
HOST: Geranium (Pelargonium sp.)
PATHOGEN: Xanthomonas hortorum pv. pelargonii
PATHOGEN SYNONYM: Xanthomonas campestris pv. pelargonii
SOURCE: M. Daughtrey
DISEASE: Bacterial blight
HOST: Geranium
Blight symptoms are affected by environmental conditions and cultivar type. Here, large, sunken, brown, circular lesions have a brownish discoloration around some lesions.
Bacterial blight | Geranium
DISEASE: Bacterial blight
HOST: Geranium (Pelargonium sp.)
PATHOGEN: Xanthomonas hortorum pv. pelargonii
PATHOGEN SYNONYM: Xanthomonas campestris pv. pelargonii
SOURCE: M. Daughtrey
DISEASE: Bacterial blight
HOST: Geranium
Geranium with wilted and necrotic leaves.
Bacterial blight | Geranium
DISEASE: Bacterial blight
HOST: Geranium (Pelargonium sp.)
PATHOGEN: Xanthomonas hortorum pv. pelargonii
PATHOGEN SYNONYM: Xanthomonas campestris pv. pelargonii
SOURCE: R. Raabe