Managing disease can be a frustrating proposition. This Guide can help you identify which disease is damaging your crop.
Leaf Rust

© Washington State University State University
Pathogen(s) causing disease:
Puccinia recondita f. sp. triticiSymptoms:
Leaf rust causes very small (about 1/32 inch long by 1/64 inch wide), orange pustules that erupt through the leaf surface. In some cases, pustules are surrounded by a narrow yellow or white halo. The pustules contain masses of powdery orange spores of the rust fungus. Spores may spill out of pustules and form a grainy orange dust on the leaf surface around the pustule. As leaves age, pustules begin to produce dark black spores instead of orange spores. These black pustules look like tar spots and are most easily seen on the lower leaf surface and leaf sheaths. Leaf rust pustules occur randomly across the leaf; this distinguishes leaf rust from stripe rust, which has narrow yellow stripes of pustules. Leaf rust typically occurs uniformly across a field.
© Purdue University, Plant and Pest Diagnostic Laboratory
Conditions:
Infection favored by moisture and cool temperatures (59-72 F).Management:
Resistant varieties, seed treatment fungicides, and plant early-maturing cultivars. Controlling volunteer wheat in the summer reduces leaf rust inoculum, but it does not guarantee freedom from rust blowing in from distant sources. Delayed planting reduces fall rust infections, but delayed maturity in the spring may lead to higher final rust levels.Sources:
Kansas State UniversityPurdue University
Crop Disease Guide
To aid your search, we've included a photo and description along with scouting and management options. And we've also added beneficial insects by crop to help in your identification process.
Choose a Disease
By Crop:
Corn
Anthracnose Leaf Blight
Seed Rot
Gray Leaf Spot
Common Corn Rust
Southern Corn Rust
Northern Corn Leaf Blight
Eyespot
Northern Leaf Spot
Southern Corn Leaf Blight
Stewart's Bacterial Disease
Anthracnose Stalk Rot
Diplodia Stalk Rot
Gibberella Stalk Rot
Fusarium Stalk Rot
Diplodia Ear Rot
Gibberella Ear Rot
Fusarium Ear Rot
Aspergillus Ear Rot
Maize Sward Mosaic
Maize Chlorotic Dwarf
Crazy Top
Seed Rot
Gray Leaf Spot
Common Corn Rust
Southern Corn Rust
Northern Corn Leaf Blight
Eyespot
Northern Leaf Spot
Southern Corn Leaf Blight
Stewart's Bacterial Disease
Anthracnose Stalk Rot
Diplodia Stalk Rot
Gibberella Stalk Rot
Fusarium Stalk Rot
Diplodia Ear Rot
Gibberella Ear Rot
Fusarium Ear Rot
Aspergillus Ear Rot
Maize Sward Mosaic
Maize Chlorotic Dwarf
Crazy Top
Wheat
American Wheat Striate Mosaic
Barley Yellow Dwarf Virus
Glume Blotch Complex
High plains mosaic pathogen
Karnal bunt
Leaf rust
Powdery mildew
Scab (fusarium head blight)
Stem rust
Strawbreaker
Stripe rust
Take-all Root Rot
Tan spot
Wheat Spindle Streak Mosaic Virus
Wheat Streak Mosaic Virus
Wheat Soilborne Mosaic Virus
Rhizoctonia Spring Blight
Common Bunt (stinking Smut)
Loose Smut
Barley Yellow Dwarf Virus
Glume Blotch Complex
High plains mosaic pathogen
Karnal bunt
Leaf rust
Powdery mildew
Scab (fusarium head blight)
Stem rust
Strawbreaker
Stripe rust
Take-all Root Rot
Tan spot
Wheat Spindle Streak Mosaic Virus
Wheat Streak Mosaic Virus
Wheat Soilborne Mosaic Virus
Rhizoctonia Spring Blight
Common Bunt (stinking Smut)
Loose Smut
Soybean
Alfalfa mosaic
Anthracnose
Bacterial blight
Bacterial pustule
Bean pod mottle
Brown Stem rot
Cercospora leaf slight
Charcoal rot
Downey mildew
Frogeye leaf spot
Fusarium wilt
Phytophthora root and stem rot
Pod and stem blight
Powdery mildew
Pythium root rot
Rhizoctonia root rot
Septoria brown spot
Soybean mosaic
Soybean rust
Stem canker
Sudden death syndrome
White mold
Anthracnose
Bacterial blight
Bacterial pustule
Bean pod mottle
Brown Stem rot
Cercospora leaf slight
Charcoal rot
Downey mildew
Frogeye leaf spot
Fusarium wilt
Phytophthora root and stem rot
Pod and stem blight
Powdery mildew
Pythium root rot
Rhizoctonia root rot
Septoria brown spot
Soybean mosaic
Soybean rust
Stem canker
Sudden death syndrome
White mold