DISEASE: Aster yellows
HOST: Wheat
Healthy head (left) and diseased head (right). Diseased seedlings may die within 2 to 3 weeks. Infected heads of surviving plants are small and sterile, with distorted awns.

Aster yellows | Wheat
DISEASE: Aster yellows
HOST: Wheat (Triticum aestivum)
PATHOGEN: 'Candidatus Phytoplasma asteris'
PATHOGEN SYNONYM: Phytoplasma Aster yellows group
SOURCE: L. N. Chiykowski
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 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