DISEASE: Alfalfa dwarf
HOST: Alfalfa
Alfalfa dwarf is characterized by stunted plants (left), usually dark blue-green in color. Xylem tissues become brown, especially when exposed to air.
Alfalfa dwarf | Alfalfa
DISEASE: Alfalfa dwarf
HOST: Alfalfa (Medicago sativa)
PATHOGEN: Xylella fastidiosa
SOURCE: R. M. Davis
DISEASE: Grain rot
HOST: Rice
Close-up of diseased grain. Infected portions of lemma and palea are purplish to dark brown.
Grain rot | Rice
DISEASE: Grain rot
HOST: Rice (Oryza sativa)
PATHOGEN: Burkholderia glumae
PATHOGEN SYNONYM: Pseudomonas glumae
SOURCE: A. Alvarez, D. Shakya
DISEASE: Grain rot
HOST: Rice
Discolored and withered hulls of infected panicles. A brown margin between the infected and healthy parts of the grain is a diagnostic feature.
Grain rot | Rice
DISEASE: Grain rot
HOST: Rice (Oryza sativa)
PATHOGEN: Burkholderia glumae
PATHOGEN SYNONYM: Pseudomonas glumae
SOURCE: M. Goto
DISEASE: Olive knot
HOST: Olive
Multiple infections of young stems. The bacterium invades vascular tissues during certain times of the year and may be isolated from branches that appear healthy.
Olive knot | Olive
DISEASE: Olive knot
HOST: Olive (Olea europaea)
PATHOGEN: Pseudomonas savastanoi pv. savastanoi
SOURCE: M. Schroth
DISEASE: Olive knot
HOST: Olive
Tree with knots/galls on branches along with twig dieback, which is associated with knots. Fusarium and Diplodia spp. infect through knots and are thought to be main reason for dieback.
Olive knot | Olive
DISEASE: Olive knot
HOST: Olive (Olea europaea)
PATHOGEN: Pseudomonas savastanoi pv. savastanoi
SOURCE: M. Schroth
DISEASE: Olive knot
HOST: Olive
Multiple infections on olive branch. Knots at this stage begin to die from the outside in and are infected by several fungi.
Olive knot | Olive
DISEASE: Olive knot
HOST: Olive (Olea europaea)
PATHOGEN: Pseudomonas savastanoi pv. savastanoi
SOURCE: M. Schroth