DISEASE: Bacterial leaf spot
HOST: Laurel (California laurel)
Leaf with dark brown, angular spots.
Bacterial leaf spot | Laurel (California laurel)
DISEASE: Bacterial leaf spot
HOST: Laurel (California laurel) (Umbellularia californica)
PATHOGEN: Pseudomonas sp.
PATHOGEN SYNONYM: Pseudomonas lauracearum
SOURCE: W. Sinclair
DISEASE: Bacterial leaf spot
HOST: Peanut
The disease causes water-soaked lesions, particularly on upper leaf surfaces. Lesions enlarge and later display brown necrotic areas. Leaflets become chlorotic and shed prematurely.
Bacterial leaf spot | Peanut
DISEASE: Bacterial leaf spot
HOST: Peanut (Arachis hypogaea)
PATHOGEN: Pseudomonas sp.
SOURCE: P. Subrahmanyam
DISEASE: Bacterial leaf spot
HOST: Verbena
Leaf with purple-brown necrotic spots.
Bacterial leaf spot | Verbena
DISEASE: Bacterial leaf spot
HOST: Verbena (Verbena sp.)
PATHOGEN: Pseudomonas sp.
SOURCE: R. Raabe
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: Rugose leaf curl
HOST: Clover
Two rugose, distorted white clover leaves and a healthy leaf. Rugose leaf curl is caused by an unidentified phloem-infecting bacterium.
Rugose leaf curl | Clover
DISEASE: Rugose leaf curl
HOST: Clover (Trifolium repens)
PATHOGEN: Phloem-infecting bacterium
SOURCE: D. Teakle