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 black spot
HOST: Mango
Mango fruit with oozing lesion (A) and raised, black lesions (B).
Bacterial black spot | Mango
DISEASE: Bacterial black spot
HOST: Mango (Mangifera indica)
PATHOGEN: Xanthomonas campestris pv. mangiferaeindicae
SOURCE: R. Ploetz
DISEASE: Bacterial black spot
HOST: Mango
Mango branch with cankers.
Bacterial black spot | Mango
DISEASE: Bacterial black spot
HOST: Mango (Mangifera indica)
PATHOGEN: Xanthomonas campestris pv. mangiferaeindicae
SOURCE: R. Ploetz
DISEASE: Bacterial black spot
HOST: Mango
Leaf with blackish spots delimited by veins.
Bacterial black spot | Mango
DISEASE: Bacterial black spot
HOST: Mango (Mangifera indica)
PATHOGEN: Xanthomonas campestris pv. mangiferaeindicae
SOURCE: APS
DISEASE: Bacterial black spot
HOST: Mango
Stem and leaf with black necroses.
Bacterial black spot | Mango
DISEASE: Bacterial black spot
HOST: Mango (Mangifera indica)
PATHOGEN: Xanthomonas campestris pv. mangiferaeindicae
SOURCE: APS
DISEASE: Bacterial black spot
HOST: Mango
Oozing cankers on young stem.
Bacterial black spot | Mango
DISEASE: Bacterial black spot
HOST: Mango (Mangifera indica)
PATHOGEN: Xanthomonas campestris pv. mangiferaeindicae
SOURCE: APS
DISEASE: Bacterial blast and black pit
HOST: Citrus (Lemon)
The term "black pit" refers to black lesions on fruit, which may be specks or large, sunken pits as seen here. They also may be light tan, later becoming reddish brown to black.
Bacterial blast and black pit | Citrus (Lemon)
DISEASE: Bacterial blast and black pit
HOST: Citrus (Lemon) (Citrus limon)
PATHOGEN: Pseudomonas syringae pv. syringae
SOURCE: J. Menge
DISEASE: Bacterial flower stalk and leaf necrosis
HOST: Onion
Dark, rotted areas of stalk and leaves caused by systemic invasion of the pathogen.
Bacterial flower stalk and leaf necrosis | Onion
DISEASE: Bacterial flower stalk and leaf necrosis
HOST: Onion (Allium cepa)
PATHOGEN: Pseudomonas marginalis pv. marginalis
SOURCE: S. Mohan