| Crop | Rice (Oryza sativa) |
| Disease | Sheath Blight |
| Pathogen | A: Rhizoctonia solani S: Thanetophorus cucumeris |
| Group | Fungi (Basidiomycota) |
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A denotes Asexual reproductive stage (Anamorph) and
S denotes Sexual reproductive stage (Teliomorph).
- Initial symptoms are noticed on leaf sheaths located near water level.
- Oval or elliptical or irregular greenish grey spots are formed on the leaf sheath.
- As the spots enlarge, the centre becomes greyish white and margin turns brown or purple brown. The spots coalesce and the leaf sheaths die showing rotting symptoms.
| Pathogen | A: Rhizoctonia solani S: Thanetophorus cucumeris |
| Mycelium | Filamentous, septate, coloured mycelium. |
| Asexual reproduction | No asexual spore. Brown colored irregularly shaped sclerotia are formed. |
| Sexual reproduction | Rarely produce Basidiospores. No sexual fruiting body. |
| Favorable Conditions | 30-32°C, RH 96-97%, Closer planting, Heavy dose of nitrogenous fertilizers |
| Primary spread | Survives as Sclerotia or mycelium in dry soil (20 months) and in moist soil (5-8 months). Spread through irrigation water. |
| Secondary spread | Soil-borne |
| Kingdom | Fungi |
| Division | Basidiomycota |
| Class | Agaricomycetes |
| Order | Cantharellales |
| Family | Ceratobasidiaceae |
| Genus | Rhizoctonia |
| Species | Rhizoctonia solani |
- Seed treatment with Pseudomonas fluorescens @ of 10g/kg of seed followed by seedling dip @ of 2.5 kg or products/ha dissolved in 100 litres and dipping for 30 minutes.
- Control of sheath blight has been mainly through the use of foliar fungicides.
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