This article is a list of diseases of the cultivated oat Avena sativa.
Bacterial diseases
| Bacterial diseases | |
|---|---|
| Bacterial blight (halo blight) | Pseudomonas coronafaciens pv. coronafaciens | 
| Bacterial stripe blight | Pseudomonas coronafaciens pv. striafaciens | 
| Black chaff and bacterial streak (stripe) | Xanthomonas campestris pv. translucens | 
Fungal diseases
| Fungal diseases | |
|---|---|
| Anthracnose | 
 Colletotrichum graminicola 
  | 
| Blast | 
 Unfavorable environmental conditions and/or any of several pathogens  | 
| Downy mildew | |
| Ergot | 
  | 
| Fusarium foot rot | |
| Head blight | 
 Bipolaris sorokiniana 
 Drechslera avenacea 
 Other Fusarium spp.  | 
| Leaf blotch and crown rot (Helminthosporium leaf blotch) | 
 
  | 
| Powdery mildew | 
 Erysiphe graminis f. sp. avenae 
  | 
| Red leather disease | 
 Spermospora avenae [anamorph]  | 
| Rhizoctonia root rot | 
  | 
| Root rot | 
 Fusarium spp.   | 
| Rust, crown | |
| Rust, stem | |
| Seedling blight | 
 Bipolaris sorokiniana  | 
| Sharp eyespot | 
  | 
| Smut, covered | 
  | 
| Smut, loose | Ustilago avenae | 
| Snow mold, pink (Fusarium patch) | 
  | 
| Snow mold, speckled or gray (Typhula blight) | |
| Speckled blotch (Septoria blight) | 
  | 
| Take-all (white head) | 
 Gaeumannomyces graminis var. avenae  | 
| Victoria blight | 
 Bipolaris victoriae   | 
Miscellaneous diseases or disorders
| Miscellaneous diseases or disorders | |
|---|---|
| Blast | Unfavorable environmental conditions and/or any of several pathogens | 
| Gray streak | Manganese deficiency | 
| Physiological leaf spot | Genetic predisposition | 
Nematodes
| Nematodes, parasitic | |
|---|---|
| Bulb and stem | |
| Cyst, oat or cereal | |
| Cyst | 
 Heterodera hordecalis  | 
| Dagger, American | |
| Lesion | |
| Pin | 
 Pratylenchus spp.  | 
| Ring | 
 Criconemella spp.   | 
| Root-knot | |
| Sheath | 
 Hemicycliophora spp.  | 
| Spiral | 
 Helicotylenchus spp.  | 
| Sting | |
| Stubby-root | |
| Stunt | 
 Quinisulcius capitatus  | 
Viruses
| Viruses | |
|---|---|
| Oat blue dwarf | Oat blue dwarf virus | 
| Oat mosaic | Oat mosaic virus | 
| Oat necrotic mottle | Oat necrotic mottle virus | 
| Oat red leaf | Barley yellow dwarf virus |