Disease Problems to Watch Out for in April


Here are some diseases we observed in the Clinic during the month of April. The hypertext links will lead you to specific information about a certain disease or about diseases in a certain crop.
Field Crops

Tobacco: Bacterial soft rot, Frenching, Heat stress, Pythium root rot, Rhizoctonia stem rot, Sclerotina collar rot, Target spot, Weather fleck
For more information, see the disease chapters in the production guides for flue-cured and burley tobacco.

Small Grains (Essential Links)

General: Cold injury, Nutritional problems, Powdery mildew, Septoria leaf spot, Virus diseases
Wheat: Cold injury, Powdery mildew, Rust, Septoria leaf spot, Take-all, Soilborne wheat mosaic

Turfgrasses (TurfFiles Publications)

General turf samples: Cold injury
Bentgrass: Dollar spot
Centipedegrass: Brown patch
Bermudagrass: Spring dead spot
Zoysiagrass: Brown patch

Woody Ornamentals

General shrubs: Cold injury, Secondary leaf spots on old leaves
Azalea & Camellia: Exobasidium leaf gall
Holly, Japanese: Black root rot, Nematodes
Boxwood, English: Dagger, Lesion and Ring nematodes, Phytophthora root rot
Cherrylaurel: Bacterial leaf spot
Dogwood: Spot anthracnose
Indian Hawthorn: Cold injury, Entomosporium leaf spot
Magnolia: Normal leaf drop, Secondary leaf spot
Magnolia, Southern: Normal leaf drop
Maple, Japanese: Sudden dying due to cold injury at soil line
Cypress, Leyland: Botryosphaeria dieback, Cypress canker
Pine & Spruce: Needle cast
Redcedar, Eastern: Cedar-apple rust
Rose: Black spot, Downy mildew, Mosaic virus, Various cane cankers/dieback

 Herbaceous Ornamentals

Greenhouse bedding plants/perennials: Botrytis blight, Cultural problems, Fertilizer injury, Impatiens necrotic spot, Pythium root rot, Rhizoctonia root/stem diseases, Sclerotinia stem rot
Bulb Crops (Tulip, Hyacinth, etc.): Bacterial soft rot of bulb, Botrytis blight of foliage, Penicillium bulb rot
English Ivy: Anthracnose, Bacterial leafspot
Geranium: Botrytis blight, Pythium root rot
Iris: Bacterial soft rot, Cladosporium leaf spot, Stem collapse
Oxalis: Rust
Pachysandra: Volutella blight

 Fruits

Apple: Fire blight
Peach: Bacterial leaf spot, Leaf curl, Ring nematodes, Root-knot nematodes
Pear: Cold injury, Entomosporium leaf spot, Old fire blight
Strawberry: Anthracnose, Angular leafspot (Xanthomonas), Multiplier disease, Powdery mildew, Various fruit rots
For more information on tree fruits see the recently revised
FDIN-002 Disease and Insect Management in the Home Orchard.

 Vegetables

Cucurbits: Gummy stem blight, Pythium damping-off, Rhizoctonia stem rot
Lettuce: Stem rot
Sweetpotato: Fusarium surface rot, Rhizopus soft rot, Scurf
Tomato (greenhouse): Botrytis blight, Early blight, Fusarium wilt, Late blight, Leaf mold, Stemphylium gray leaf spot, Stem rot/timber rot (Sclerotinia)
Vegetable transplants: Botrytis blight, Fertilizer injury, Rhizoctonia and Pythium damping-off,
Sclerotinia stem rot
Watermelon: Gummy stem blight

Other Links

Plant Clinic Summaries
Plant Disease Information Notes
Plant Disease and Insect Clinic

Last update: 15 January 2004