DISEASE: Head rot (Jelly rot)
HOST: Lettuce
Sliced head of lettuce. Typical symptoms are a translucent appearance and browning or jelly rot of the stalk (crown).
Head rot (Jelly rot) | Lettuce
DISEASE: Head rot (Jelly rot)
HOST: Lettuce (Lactuca sativa)
PATHOGEN: Pectobacterium carotovorum
PATHOGEN SYNONYM: Erwinia carotovora subsp. carotovora
SOURCE: J. Cho, A. Alvarez
DISEASE: Head rot (Jelly rot)
HOST: Lettuce
Advanced stage of lettuce stalk rot (crown).
Head rot (Jelly rot) | Lettuce
DISEASE: Head rot (Jelly rot)
HOST: Lettuce (Lactuca sativa)
PATHOGEN: Pectobacterium carotovorum
PATHOGEN SYNONYM: Erwinia carotovora subsp. carotovora
SOURCE: J. Cho, A. Alvarez
DISEASE: Head rot (Jelly rot)
HOST: Lettuce
Head rot of lettuce first appears as rapid wilt of outer wrapper leaves. Wilt is caused by collapse of vascular tissues, which develop a pinkish to brown discoloration.
Head rot (Jelly rot) | Lettuce
DISEASE: Head rot (Jelly rot)
HOST: Lettuce (Lactuca sativa)
PATHOGEN: Pectobacterium carotovorum
PATHOGEN SYNONYM: Erwinia carotovora subsp. carotovora
SOURCE: L. Fucikovsky
DISEASE: Oak leaf scorch
HOST: Oak
Oak with scorched leaf tips.
Oak leaf scorch | Oak
DISEASE: Oak leaf scorch
HOST: Oak (Quercus kelloggii)
PATHOGEN: Xylella fastidiosa
SOURCE: S. Kostka
DISEASE: Oak leaf scorch
HOST: Oak
Leaf with brown, marginal necrosis resembling a burn.
Oak leaf scorch | Oak
DISEASE: Oak leaf scorch
HOST: Oak (Quercus rubra)
PATHOGEN: Xylella fastidiosa
SOURCE: W. Sinclair
DISEASE: Oak leaf scorch
HOST: Oak
Diseased tree with brownish, scorched leaves.
Oak leaf scorch | Oak
DISEASE: Oak leaf scorch
HOST: Oak (Quercus rubra)
PATHOGEN: Xylella fastidiosa
SOURCE: W. Sinclair
DISEASE: Witches'-broom
HOST: Alfalfa
Alfalfa plant (center) exhibiting stunting and proliferation of stems. Other symptoms are small, rounded, chlorotic, often puckered leaves and a yellowish cast.
Witches'-broom | Alfalfa
DISEASE: Witches'-broom
HOST: Alfalfa (Medicago sativa)
PATHOGEN: 'Candidatus Phytoplasma trifolii'
PATHOGEN SYNONYM: Phytoplasma Clover proliferation group
SOURCE: S. Thomson
DISEASE: Witches'-broom
HOST: Alfalfa
Young plant (left) with small, numerous stems (witches'-broom). Healthy stems (right).
Witches'-broom | Alfalfa
DISEASE: Witches'-broom
HOST: Alfalfa (Medicago sativa)
PATHOGEN: 'Candidatus Phytoplasma trifolii'
PATHOGEN SYNONYM: Phytoplasma Clover proliferation group
SOURCE: S. Thomson
DISEASE: Witches'-broom
HOST: Cactus
Witches'-broom of Opuntia cactus.
Witches'-broom | Cactus
DISEASE: Witches'-broom
HOST: Cactus (Opuntia sp.)
PATHOGEN: 'Candidatus Phytoplasma' sp.
PATHOGEN SYNONYM: Phytoplasma (undefined)
SOURCE: R. McCoy, M. Davis