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: Aster yellows
HOST: Squash
Diagnostic characteristics for the disease are yellowing of young leaves, proliferation of secondary shoots, and rigid erect habit. Leaves are misshapen and smaller than normal and have stiff, thick laminae.
Aster yellows | Squash
DISEASE: Aster yellows
HOST: Squash (Cucurbita sp.)
PATHOGEN: 'Candidatus Phytoplasma asteris'
PATHOGEN SYNONYM: Phytoplasma Aster yellows group
SOURCE: S. Miller
DISEASE: Bacterial finger-tip rot
HOST: Banana
Cross sections of fruit with internal discoloration and rot. This disease is also known as Mokillo disease.
Bacterial finger-tip rot | Banana
DISEASE: Bacterial finger-tip rot
HOST: Banana (Musa sp.)
PATHOGEN: Burkholderia cenocepacia
PATHOGEN SYNONYM: Pseudomonas cenocepacia
SOURCE: I. Buddenhagen
DISEASE: Bacterial finger-tip rot
HOST: Banana
Longitudinal sections of fruit with internal discoloration and rot. Healthy (right).
Bacterial finger-tip rot | Banana
DISEASE: Bacterial finger-tip rot
HOST: Banana (Musa sp.)
PATHOGEN: Burkholderia cenocepacia
PATHOGEN SYNONYM: Pseudomonas cenocepacia
SOURCE: I. Buddenhagen
DISEASE: Bacterial finger-tip rot
HOST: Banana
Diseased banana hand with external discoloration.
Bacterial finger-tip rot | Banana
DISEASE: Bacterial finger-tip rot
HOST: Banana (Musa sp.)
PATHOGEN: Burkholderia cenocepacia
PATHOGEN SYNONYM: Pseudomonas cenocepacia
SOURCE: I. Buddenhagen
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