DISEASE: Bacterial blight (Boll rot)
HOST: Cotton
Boll rot first appears as raised, water-soaked lesions, which become sunken and turn brown to black with time.
Bacterial blight (Boll rot) | Cotton
DISEASE: Bacterial blight (Boll rot)
HOST: Cotton (Gossypium barbadense)
PATHOGEN: Xanthomonas citri subsp. malvacearum
PATHOGEN SYNONYM: Xanthomonas campestris pv. malvacearum
SOURCE: A. Hayward
DISEASE: Bacterial blight (Boll rot)
HOST: Cotton
Infection of bolls causes premature opening and increased susceptibility to secondary, saprophytic microorganisms that cause rot. Note discolored cotton.
Bacterial blight (Boll rot) | Cotton
DISEASE: Bacterial blight (Boll rot)
HOST: Cotton (Gossypium barbadense)
PATHOGEN: Xanthomonas citri subsp. malvacearum
PATHOGEN SYNONYM: Xanthomonas campestris pv. malvacearum
SOURCE: APS
DISEASE: Sweet potato little leaf
HOST: Sweet potato
Infected plant (left) and healthy plant (right).
Sweet potato little leaf | Sweet potato
DISEASE: Sweet potato little leaf
HOST: Sweet potato (Ipomoea batatas)
PATHOGEN: 'Candidatus Phytoplasma aurantifolia'
PATHOGEN SYNONYM: Phytoplasma Peanut witches'-broom group
SOURCE: R. McCoy, M. Davis
DISEASE: Varnish spot
HOST: Lettuce
Leaf with large brown and small, shiny, dark brown necrotic spots that spread in size and later dry out.
Varnish spot | Lettuce
DISEASE: Varnish spot
HOST: Lettuce (Lactuca sativa)
PATHOGEN: Pseudomonas cichorii
SOURCE: S. Miller
DISEASE: Varnish spot
HOST: Lettuce
Advanced stage of disease with large, brown necrotic areas. They most often are along veins. Outermost leaves of the head usually are not affected.
Varnish spot | Lettuce
DISEASE: Varnish spot
HOST: Lettuce (Lactuca sativa)
PATHOGEN: Pseudomonas cichorii
SOURCE: K. Ohata, M. Goto