DISEASE: Bacterial stem and root rot
HOST: Sweet potato
Collapse of stems and roots caused by systemic activity of the pathogen.

Bacterial stem and root rot | Sweet potato
DISEASE: Bacterial stem and root rot
HOST: Sweet potato (Ipomoea batatas)
PATHOGEN: Dickeya sp.
PATHOGEN SYNONYM: Erwinia chrysanthemi
SOURCE: N. Schaad
DISEASE: Bacterial stem and root rot
HOST: Sweet potato
Rot and collapse of stem, petioles, and leaves caused by systemic infection.

Bacterial stem and root rot | Sweet potato
DISEASE: Bacterial stem and root rot
HOST: Sweet potato (Ipomoea batatas)
PATHOGEN: Dickeya sp.
PATHOGEN SYNONYM: Erwinia chrysanthemi
SOURCE: N. Schaad
DISEASE: Bacterial stem and root rot
HOST: Sweet potato
Rot and internal discoloration of tuber.

Bacterial stem and root rot | Sweet potato
DISEASE: Bacterial stem and root rot
HOST: Sweet potato (Ipomoea batatas)
PATHOGEN: Dickeya sp.
PATHOGEN SYNONYM: Erwinia chrysanthemi
SOURCE: C. Clark
DISEASE: Carrot yellows
HOST: Carrot
Flowers with shoot proliferation (witches’-broom) (left). Healthy flower (right). Virescence and phyllody of flower parts are common.

Carrot yellows | Carrot
DISEASE: Carrot yellows
HOST: Carrot (Daucus carota)
PATHOGEN: 'Candidatus Phytoplasma asteris'
PATHOGEN SYNONYM: Phytoplasma Aster yellows group
SOURCE: M. Schroth
DISEASE: Carrot yellows
HOST: Carrot
Carrot with proliferation of roots. Initial symptoms include yellowing and narrowing of veins of young leaves. The entire leaf later becomes necrotic.

Carrot yellows | Carrot
DISEASE: Carrot yellows
HOST: Carrot (Daucus carota)
PATHOGEN: 'Candidatus Phytoplasma asteris'
PATHOGEN SYNONYM: Phytoplasma Aster yellows group
SOURCE: G. S. Abawi
DISEASE: Citrus canker
HOST: Citrus (Grapefruit)
Grapefruit with corky, raised lesions.

Citrus canker | Citrus (Grapefruit)
DISEASE: Citrus canker
HOST: Citrus (Grapefruit) (Citrus paradisi)
PATHOGEN: Xanthomonas citri subsp. citri
PATHOGEN SYNONYM: Xanthomonas citri
SOURCE: T. Gottwald
DISEASE: Citrus canker
HOST: Citrus (Lemon)
Lower leaf with raised, corkylike lesions surrounded by dark brown halos, one of the diagnostic symptoms of citrus canker.

Citrus canker | Citrus (Lemon)
DISEASE: Citrus canker
HOST: Citrus (Lemon) (Citrus limon)
PATHOGEN: Xanthomonas citri subsp. citri
PATHOGEN SYNONYM: Xanthomonas citri
SOURCE: T. Gottwald
DISEASE: Citrus canker
HOST: Citrus (Orange)
Leaf with leaf miner tunnels and numerous cankerlike lesions.

Citrus canker | Citrus (Orange)
DISEASE: Citrus canker
HOST: Citrus (Orange) (Citrus sinensis)
PATHOGEN: Xanthomonas citri subsp. citri
PATHOGEN SYNONYM: Xanthomonas citri
SOURCE: T. Gottwald
DISEASE: Citrus canker
HOST: Citrus (Orange)
Upper side of leaves with corky, raised lesions surrounded by yellow halos, a late stage of disease. Such infections usually are visible on lower sides of leaves first and soon after on upper sides.

Citrus canker | Citrus (Orange)
DISEASE: Citrus canker
HOST: Citrus (Orange) (Citrus sinensis)
PATHOGEN: Xanthomonas citri subsp. citri
PATHOGEN SYNONYM: Xanthomonas citri
SOURCE: J. H. Graham