DISEASE: Aster yellows
HOST: Onion
Infected plants with yellowish, malformed leaves.
Aster yellows | Onion
DISEASE: Aster yellows
HOST: Onion (Allium cepa)
PATHOGEN: 'Candidatus Phytoplasma asteris'
PATHOGEN SYNONYM: Phytoplasma Aster yellows group
SOURCE: R. Rowe
DISEASE: Aster yellows
HOST: Onion
Onion flower with unusual symptoms (left) compared with healthy inflorescence (right). Flowers are distorted and often have abnormally long pedicels. Young leaves may have yellow streaks or a general yellowing of basal portions.
Aster yellows | Onion
DISEASE: Aster yellows
HOST: Onion (Allium cepa)
PATHOGEN: 'Candidatus Phytoplasma asteris'
PATHOGEN SYNONYM: Phytoplasma Aster yellows group
SOURCE: R. Raabe
DISEASE: Bacterial dieback of nectarine
HOST: Nectarine
Dark cankers on last year's twig. Symptoms of bacterial dieback of nectarine are identical to those of bacterial dieback of peach.
Bacterial dieback of nectarine | Nectarine
DISEASE: Bacterial dieback of nectarine
HOST: Nectarine (Prunus persica var. nucipersica)
PATHOGEN: Pseudomonas syringae pv. persicae
SOURCE: J. Young
DISEASE: Bacterial dieback of nectarine
HOST: Nectarine
Diseased young twigs.
Bacterial dieback of nectarine | Nectarine
DISEASE: Bacterial dieback of nectarine
HOST: Nectarine (Prunus persica var. nucipersica)
PATHOGEN: Pseudomonas syringae pv. persicae
SOURCE: J. Young
DISEASE: Bacterial dieback of nectarine
HOST: Nectarine
Bacterial invasion of trunk caused reddish brown discolored area. Symptoms of bacterial dieback of nectarine are identical to those of bacterial dieback of peach.
Bacterial dieback of nectarine | Nectarine
DISEASE: Bacterial dieback of nectarine
HOST: Nectarine (Prunus persica var. nucipersica)
PATHOGEN: Pseudomonas syringae pv. persicae
SOURCE: J. Young
DISEASE: Bacterial dieback of nectarine
HOST: Nectarine
Discolored vascular tissues and gummosis on infected twig.
Bacterial dieback of nectarine | Nectarine
DISEASE: Bacterial dieback of nectarine
HOST: Nectarine (Prunus persica var. nucipersica)
PATHOGEN: Pseudomonas syringae pv. persicae
SOURCE: J. Young
DISEASE: Bacterial dieback of nectarine
HOST: Nectarine
Symptoms of the disease include leaf spots (top leaf). Similar appearing leaf spots may be caused by Xanthomonas arboricola pv. pruni (bottom leaf).
Bacterial dieback of nectarine | Nectarine
DISEASE: Bacterial dieback of nectarine
HOST: Nectarine (Prunus persica var. nucipersica)
PATHOGEN: Pseudomonas syringae pv. persicae
SOURCE: J. Young
DISEASE: Bacterial dieback of nectarine
HOST: Nectarine
Dying tree caused by systemic invasion of the bacterium. Symptoms of bacterial dieback of nectarine are identical to those of bacterial dieback of peach.
Bacterial dieback of nectarine | Nectarine
DISEASE: Bacterial dieback of nectarine
HOST: Nectarine (Prunus persica var. nucipersica)
PATHOGEN: Pseudomonas syringae pv. persicae
SOURCE: J. Young
DISEASE: Bacterial flower stalk and leaf necrosis
HOST: Onion
Dark, rotted areas of stalk and leaves caused by systemic invasion of the pathogen.
Bacterial flower stalk and leaf necrosis | Onion
DISEASE: Bacterial flower stalk and leaf necrosis
HOST: Onion (Allium cepa)
PATHOGEN: Pseudomonas marginalis pv. marginalis
SOURCE: S. Mohan