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: Bacterial dieback of peach
HOST: Peach
Dark cankers on last year's twig. This leads to blighting of buds the following year.
Bacterial dieback of peach | Peach
DISEASE: Bacterial dieback of peach
HOST: Peach (Prunus persica)
PATHOGEN: Pseudomonas syringae pv. persicae
SOURCE: J. Young
DISEASE: Bacterial leaf spot
HOST: Alfalfa
Stems with necrotic lesions.
Bacterial leaf spot | Alfalfa
DISEASE: Bacterial leaf spot
HOST: Alfalfa (Medicago sativa)
PATHOGEN: Xanthomonas alfalfae subsp. alfalfae
PATHOGEN SYNONYM: Xanthomonas campestris pv. alfalfae
SOURCE: APS
DISEASE: Bacterial leaf spot
HOST: Alfalfa
Leaves with brown necrotic spots. Stems have water-soaked spots.
Bacterial leaf spot | Alfalfa
DISEASE: Bacterial leaf spot
HOST: Alfalfa (Medicago sativa)
PATHOGEN: Xanthomonas alfalfae subsp. alfalfae
PATHOGEN SYNONYM: Xanthomonas campestris pv. alfalfae
SOURCE: S. Thomson
DISEASE: Bacterial leaf spot
HOST: Alfalfa
Leaves with both water-soaked and necrotic spots.
Bacterial leaf spot | Alfalfa
DISEASE: Bacterial leaf spot
HOST: Alfalfa (Medicago sativa)
PATHOGEN: Xanthomonas alfalfae subsp. alfalfae
PATHOGEN SYNONYM: Xanthomonas campestris pv. alfalfae
SOURCE: APS
DISEASE: Bacterial leaf spot
HOST: Alfalfa
Leaves with necrotic, brownish paperlike areas.
Bacterial leaf spot | Alfalfa
DISEASE: Bacterial leaf spot
HOST: Alfalfa (Medicago sativa)
PATHOGEN: Xanthomonas alfalfae subsp. alfalfae
PATHOGEN SYNONYM: Xanthomonas campestris pv. alfalfae
SOURCE: APS
DISEASE: Bacterial spot
HOST: Peach
Pitted fruit caused by late season infection.
Bacterial spot | Peach
DISEASE: Bacterial spot
HOST: Peach (Prunus persica)
PATHOGEN: Xanthomonas arboricola pv. pruni
PATHOGEN SYNONYM: Xanthomonas campestris pv. pruni
SOURCE: E. Zehr
DISEASE: Bacterial spot
HOST: Peach
Fruit infected late in the season.
Bacterial spot | Peach
DISEASE: Bacterial spot
HOST: Peach (Prunus persica)
PATHOGEN: Xanthomonas arboricola pv. pruni
PATHOGEN SYNONYM: Xanthomonas campestris pv. pruni
SOURCE: T. Burr
DISEASE: Bacterial spot
HOST: Peach
Reddish lesions on young twig (left). Dead buds are visible (right), the result of previous year's infection of twig.
Bacterial spot | Peach
DISEASE: Bacterial spot
HOST: Peach (Prunus persica)
PATHOGEN: Xanthomonas arboricola pv. pruni
PATHOGEN SYNONYM: Xanthomonas campestris pv. pruni
SOURCE: D. Ritchie