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 blight
HOST: Geranium
Leaf with many necrotic spots and chlorotic V-shaped lesions.
Bacterial blight | Geranium
DISEASE: Bacterial blight
HOST: Geranium (Pelargonium sp.)
PATHOGEN: Xanthomonas hortorum pv. pelargonii
PATHOGEN SYNONYM: Xanthomonas campestris pv. pelargonii
SOURCE: M. Daughtrey
DISEASE: Bacterial blight
HOST: Geranium
Blight symptoms are affected by environmental conditions and cultivar type. Here, large, sunken, brown, circular lesions have a brownish discoloration around some lesions.
Bacterial blight | Geranium
DISEASE: Bacterial blight
HOST: Geranium (Pelargonium sp.)
PATHOGEN: Xanthomonas hortorum pv. pelargonii
PATHOGEN SYNONYM: Xanthomonas campestris pv. pelargonii
SOURCE: M. Daughtrey
DISEASE: Bacterial blight
HOST: Geranium
Geranium with wilted and necrotic leaves.
Bacterial blight | Geranium
DISEASE: Bacterial blight
HOST: Geranium (Pelargonium sp.)
PATHOGEN: Xanthomonas hortorum pv. pelargonii
PATHOGEN SYNONYM: Xanthomonas campestris pv. pelargonii
SOURCE: R. Raabe
DISEASE: Bacterial blight
HOST: Geranium
Left and center leaves have spots, whereas leaf on right also has blight symptoms.
Bacterial blight | Geranium
DISEASE: Bacterial blight
HOST: Geranium (Pelargonium sp.)
PATHOGEN: Xanthomonas hortorum pv. pelargonii
PATHOGEN SYNONYM: Xanthomonas campestris pv. pelargonii
SOURCE: M. Shurtleff
DISEASE: Bacterial blight
HOST: Geranium
Severely blighted leaves, stems, and petioles.
Bacterial blight | Geranium
DISEASE: Bacterial blight
HOST: Geranium (Pelargonium sp.)
PATHOGEN: Xanthomonas hortorum pv. pelargonii
PATHOGEN SYNONYM: Xanthomonas campestris pv. pelargonii
SOURCE: S. Thomson
DISEASE: Bacterial blight
HOST: Geranium
Systemically infected plant with longitudinal lesions on stem.
Bacterial blight | Geranium
DISEASE: Bacterial blight
HOST: Geranium (Pelargonium sp.)
PATHOGEN: Xanthomonas hortorum pv. pelargonii
PATHOGEN SYNONYM: Xanthomonas campestris pv. pelargonii
SOURCE: H. Vruggink, J. van der Wolf
DISEASE: Bacterial blight
HOST: Geranium
Lesions surrounded by yellow areas are characteristic of advanced stage of disease.
Bacterial blight | Geranium
DISEASE: Bacterial blight
HOST: Geranium (Pelargonium sp.)
PATHOGEN: Xanthomonas hortorum pv. pelargonii
PATHOGEN SYNONYM: Xanthomonas campestris pv. pelargonii
SOURCE: M. Geesteranus, J. van der Wolf
DISEASE: Bacterial blight
HOST: Geranium
Small, dark lesions and large, V-shaped necrotic areas typically occur during early stages of disease.
Bacterial blight | Geranium
DISEASE: Bacterial blight
HOST: Geranium (Pelargonium sp.)
PATHOGEN: Xanthomonas hortorum pv. pelargonii
PATHOGEN SYNONYM: Xanthomonas campestris pv. pelargonii
SOURCE: M. Daughtrey