Bacterial Wilt

Older stands

Yes

Plants stunted and yellowed, usually scattered

Yellow-brown ring of  discoloration of outside of tap root, stand loss

Resistant varieties

Anthracnose

Warm, moist

Yes,  Dead stems may develop shepherd's crook

Oval sunken tan lesions with dark borders. Lesions can girdle and kill stems.

Crown and tap roots decay with blue black color

Resistant varieties

Fusarium wilt

Injured roots, warm wet soils

Yes, sometimes only one side of plant.  Wilted plants initially may recover overnight

Wilted plants not stunted like bacterial wilt. Leaves become yellow and bleached sometimes with a  reddish hue

Stele has brick red colored discoloration. Initially this is streaked.

Resistant varieties

Soil fertility

Insect control

Phytophthora root rot

Wet soils

Yes, may recover with cool temperatures and water

Seedlings:  Water soaked and death

Mature plants: Plants suddenly wilt in hot dry conditions.  Plants can be bleached and yellow -red

Rotted lateral and tap roots

Resistant varieties

Drainage

Soil fertility

Avoid plant stress

Aphanomyces  root rot

Wet soils

No

Seedlings: Yellow cotyledons water-soaking of stems, stunting

Mature plants: Yellowed, slow re-growth, Often chronic infection

Rotted lateral roots

Resistant varieties

Drainage

Verticillium wilt

2^nd year and older stands. Rapid spread once in field

Leaflets only

Yellow leaflet tips, leaflets die rolled length-wise with a green stem.

Often a brown, discolored vascular ring.

Resistant varieties Crop rotation Sanitation

Sclerotinia stem rot

New seedings, especially those seeded in summer.  Cool wet conditions

No

White, cottony mycelium on the outside of the stem. Sclerotia usually visible. Lower stems and sometimes crowns softened and discolored

Not a root pathogen

No resistance known.  Rotation to grass crops. Spring seeding usually less disease