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: Marginal leaf blight
HOST: Lettuce
Marginal leaf blight first appears as slimy wilting of leaf margins. Small, reddish lesions may be seen on leaf blades. Infected tissues turn brown to black in time.

Marginal leaf blight | Lettuce
DISEASE: Marginal leaf blight
HOST: Lettuce (Lactuca sativa)
PATHOGEN: Pseudomonas marginalis
SOURCE: L. Fucikovsky