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: Soybean
Leaves with yellowish brown necrotic lesions. Lesions also may be yellow to light brown and bordered by yellowish green halos. Lesions occur on stems, petioles, and pods.

Bacterial blight | Soybean
DISEASE: Bacterial blight
HOST: Soybean (Glycine max)
PATHOGEN: Pseudomonas syringae pv. glycinea
SOURCE: J. B. Sinclair
DISEASE: Bacterial canker (Leaf and fruit spot)
HOST: Kiwi
Diseased blossoms, a stage of bacterial canker.

Bacterial canker (Leaf and fruit spot) | Kiwi
DISEASE: Bacterial canker (Leaf and fruit spot)
HOST: Kiwi (Actinidia chinensis)
PATHOGEN: Pseudomonas syringae pv. actinidiae
SOURCE: J. Young
DISEASE: Bacterial canker (Leaf and fruit spot)
HOST: Kiwi
Leaf spot stage of the disease with small, brown lesions with yellow halos.

Bacterial canker (Leaf and fruit spot) | Kiwi
DISEASE: Bacterial canker (Leaf and fruit spot)
HOST: Kiwi (Actinidia chinensis)
PATHOGEN: Pseudomonas syringae pv. actinidiae
SOURCE: M. Goto
DISEASE: Bacterial canker (Leaf and fruit spot)
HOST: Kiwi
Leaf spots on young leaves. Note dark brown to black lesions on lower surface (left) and similar lesions on upper surface but with yellow halos (right).

Bacterial canker (Leaf and fruit spot) | Kiwi
DISEASE: Bacterial canker (Leaf and fruit spot)
HOST: Kiwi (Actinidia chinensis)
PATHOGEN: Pseudomonas syringae pv. actinidiae
SOURCE: J. Young
DISEASE: Bacterial canker (Leaf and fruit spot)
HOST: Kiwi
Rusty-colored exudate oozing from cankers on infected trunk.

Bacterial canker (Leaf and fruit spot) | Kiwi
DISEASE: Bacterial canker (Leaf and fruit spot)
HOST: Kiwi (Actinidia chinensis)
PATHOGEN: Pseudomonas syringae pv. actinidiae
SOURCE: M. Goto
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
DISEASE: Bacterial flower stalk and leaf necrosis
HOST: Onion
Gray-brown rot of onion after inoculation. Disease starts as small, water-soaked lesions that later develop into slimy, gray-brown rot. The disease progresses downward from the stalk and may rot the entire bulb.

Bacterial flower stalk and leaf necrosis | Onion
DISEASE: Bacterial flower stalk and leaf necrosis
HOST: Onion (Allium cepa)
PATHOGEN: Pseudomonas marginalis pv. marginalis
SOURCE: R. Gitaitis