DISEASE: Bacterial blight (Leaf spot)
HOST: Clover
Diseased leaf with elongated, reddish brown lesions, especially numerous on the margins.
Bacterial blight (Leaf spot) | Clover
DISEASE: Bacterial blight (Leaf spot)
HOST: Clover (Trifolium alexandrinum)
PATHOGEN: Pseudomonas syringae pv. syringae
SOURCE: M. Shurtleff
DISEASE: Corky root
HOST: Lettuce
Corky root causes a reduction in size of lettuce heads and root systems; susceptible cultivar (right) and resistant cultivar (left).
Corky root | Lettuce
DISEASE: Corky root
HOST: Lettuce (Lactuca sativa)
PATHOGEN: Sphingomonas suberifaciens
PATHOGEN SYNONYM: Rhizomonas suberifaciens
SOURCE: E. J. Ryder
DISEASE: Corky root
HOST: Lettuce
Close-up of root with malformed, corky appearance and longitudinal ridges of brown tissues.
Corky root | Lettuce
DISEASE: Corky root
HOST: Lettuce (Lactuca sativa)
PATHOGEN: Sphingomonas suberifaciens
PATHOGEN SYNONYM: Rhizomonas suberifaciens
SOURCE: A. van Bruggen
DISEASE: Corky root
HOST: Lettuce
Initial symptoms of disease are yellow lesions on taproot and main laterals. Greenish brown bands occur around roots. Root pith may become brown and hollow.
Corky root | Lettuce
DISEASE: Corky root
HOST: Lettuce (Lactuca sativa)
PATHOGEN: Sphingomonas suberifaciens
PATHOGEN SYNONYM: Rhizomonas suberifaciens
SOURCE: A. van Bruggen
DISEASE: Corky root
HOST: Lettuce
Differences in corky root symptoms between susceptible cultivar (right) and resistant cultivar (left).
Corky root | Lettuce
DISEASE: Corky root
HOST: Lettuce (Lactuca sativa)
PATHOGEN: Sphingomonas suberifaciens
PATHOGEN SYNONYM: Rhizomonas suberifaciens
SOURCE: E. Ryder
DISEASE: Purple stain
HOST: Papaya
Purple pigmentation of internal tissues near peduncle end of fruits. Pigmentation and yellow translucence of papaya flesh are more evident of fruit on right.
Purple stain | Papaya
DISEASE: Purple stain
HOST: Papaya (Carica papaya)
PATHOGEN: Pantoea agglomerans
PATHOGEN SYNONYM: Erwinia herbicola
SOURCE: M. Nelson
DISEASE: Purple stain
HOST: Papaya
Purple pigmentation of internal tissues.
Purple stain | Papaya
DISEASE: Purple stain
HOST: Papaya (Carica papaya)
PATHOGEN: Pantoea agglomerans
PATHOGEN SYNONYM: Erwinia herbicola
SOURCE: M. Nelson
DISEASE: Purple stain
HOST: Papaya
Another view of purple discoloration at peduncle end. Bacteria are found in vascular tissues and latex ducts.
Purple stain | Papaya
DISEASE: Purple stain
HOST: Papaya (Carica papaya)
PATHOGEN: Pantoea agglomerans
PATHOGEN SYNONYM: Erwinia herbicola
SOURCE: K. Nishijima
DISEASE: Purple stain
HOST: Papaya
Cross section of fruit exhibiting purplish discoloration in latex ducts.
Purple stain | Papaya
DISEASE: Purple stain
HOST: Papaya (Carica papaya)
PATHOGEN: Pantoea agglomerans
PATHOGEN SYNONYM: Erwinia herbicola
SOURCE: M. Nelson, A. Alvarez