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: Almond leaf scorch
HOST: Almond
Light brown necrotic (scorched) areas on curling leaves.
Almond leaf scorch | Almond
DISEASE: Almond leaf scorch
HOST: Almond (Prunus dulcis)
PATHOGEN: Xylella fastidiosa
SOURCE: W. Sinclair
DISEASE: Almond leaf scorch
HOST: Almond
Dying almond trees with scorched appearance. Initial symptoms are marginal chlorosis, usually late in the year. Scorch often is first noted at leaf tips, symptoms worsen, and terminal branches may die.
Almond leaf scorch | Almond
DISEASE: Almond leaf scorch
HOST: Almond (Prunus dulcis)
PATHOGEN: Xylella fastidiosa
SOURCE: R. Davis, M. Davis
DISEASE: Bacterial leaf scorch
HOST: Pecan
Pecan with necrotic scorched leaves with distinct dark lines between healthy and diseased tissues.
Bacterial leaf scorch | Pecan
DISEASE: Bacterial leaf scorch
HOST: Pecan (Carya illinoinensis)
PATHOGEN: Xylella fastidiosa
SOURCE: T. Brenneman
DISEASE: Bacterial leaf scorch
HOST: Sycamore
Sycamore with scorched leaves and dieback of small branches.
Bacterial leaf scorch | Sycamore
DISEASE: Bacterial leaf scorch
HOST: Sycamore (Platanus occidentalis)
PATHOGEN: Xylella fastidiosa
SOURCE: W. Sinclair
DISEASE: Bacterial leaf scorch
HOST: Sycamore
Close-up of scorched leaves.
Bacterial leaf scorch | Sycamore
DISEASE: Bacterial leaf scorch
HOST: Sycamore (Platanus occidentalis)
PATHOGEN: Xylella fastidiosa
SOURCE: W. Sinclair
DISEASE: Bacterial wilt
HOST: Bean
Bean leaf with white pustules following inoculation. Stem inoculation causes veinal yellowing and necrosis of leaves. Infected seed may be purple or yellow.
Bacterial wilt | Bean
DISEASE: Bacterial wilt
HOST: Bean (Phaseolus vulgaris)
PATHOGEN: Curtobacterium flaccumfaciens pv. flaccumfaciens
SOURCE: L. Claflin
DISEASE: Bacterial wilt
HOST: Bean
Leaves with interveinal chlorosis and necrosis. Healthy (right).
Bacterial wilt | Bean
DISEASE: Bacterial wilt
HOST: Bean (Phaseolus vulgaris)
PATHOGEN: Curtobacterium flaccumfaciens pv. flaccumfaciens
SOURCE: APS
DISEASE: Bacterial wilt
HOST: Bean
Bean seeds infected with orange (upper right), violet (upper left), and yellow (lower left) variants of Curtobacterium flaccumfaciens. White seed in the lower right is healthy.
Bacterial wilt | Bean
DISEASE: Bacterial wilt
HOST: Bean (Phaseolus vulgaris)
PATHOGEN: Curtobacterium flaccumfaciens pv. flaccumfaciens
SOURCE: APS