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: Strawberry lethal decline
HOST: Strawberry
Diseased plant with bronzing of older leaves and upward rolling or cupping of younger leaves. Leaves are chlorotic on upper surfaces and reddish or purplish on lower surfaces. In time, the entire plant dies.

Strawberry lethal decline | Strawberry
DISEASE: Strawberry lethal decline
HOST: Strawberry (Fragaria × ananassa)
PATHOGEN: 'Candidatus Phytoplasma' sp.
PATHOGEN SYNONYM: Phytoplasma (undefined)
SOURCE: H. Schwartz
DISEASE: Xanthomonas leaf blight
HOST: Onion
This was the first photo of onion leaf blight, which was considered a controversial finding for 10 years until an outbreak occurred in the West Indies.

Xanthomonas leaf blight | Onion
DISEASE: Xanthomonas leaf blight
HOST: Onion (Allium cepa)
PATHOGEN: Xanthomonas axonopodis pv. allii
PATHOGEN SYNONYM: Xanthomonas campestris pv. allii
SOURCE: A. Alvarez
DISEASE: Xanthomonas leaf blight
HOST: Onion
Diseased leaf with necrotic internal tissues.

Xanthomonas leaf blight | Onion
DISEASE: Xanthomonas leaf blight
HOST: Onion (Allium cepa)
PATHOGEN: Xanthomonas axonopodis pv. allii
PATHOGEN SYNONYM: Xanthomonas campestris pv. allii
SOURCE: A. Alvarez
DISEASE: Xanthomonas leaf blight
HOST: Onion
Onions with brown, necrotic, blighted leaves.

Xanthomonas leaf blight | Onion
DISEASE: Xanthomonas leaf blight
HOST: Onion (Allium cepa)
PATHOGEN: Xanthomonas axonopodis pv. allii
PATHOGEN SYNONYM: Xanthomonas campestris pv. allii
SOURCE: H. Schwartz
DISEASE: Xanthomonas leaf blight
HOST: Onion
Onions with severely blighted leaves.

Xanthomonas leaf blight | Onion
DISEASE: Xanthomonas leaf blight
HOST: Onion (Allium cepa)
PATHOGEN: Xanthomonas axonopodis pv. allii
PATHOGEN SYNONYM: Xanthomonas campestris pv. allii
SOURCE: H. Schwartz