Agricultural crops :: Cereals :: Ragi diseases
Foot Rot or Wilt: Sclerotium Rolfsii
Symptom:
- The infected plants remain green and stunted.
- The fungus attacks the basal stem portion and later the leaf sheath and culm.
- The infected portion becomes soft and dark brown in colour.
- The fungus is seen to grow in between the sheath and stem on the lesions.
- The plant ultimately dies.
- On the surface of lesions, small, spherical, dark coloured sclerotia are formed.
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| DARK BROWN SHEATH |
STUNTED PLANT |
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Identification of pathogen:
- The pathogen forms a submerged vegetative mycelium consisting of single hyphae and an aerial mycelium composed of both single hyphae and hyphal strands.
- Sclerotial initials are formed on these hyphal strands
- Sclerotia (0.5-2.0mm diameter) begin to develop after 4-7 days of mycelial growth (2,10). Initially a felty white appearance, sclerotia quickly melanize to a dark brown coloration
- Sclerotia contain viable hyphae and serve as primary inoculum for disease development.
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| Mycelium of Sclerotium Rolfsii |
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Hyphal segement |
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Management:
- Keeping the plants healthy and robust, and providing good drainage and other optimum soil conditions, help to avoid the disease.
- Deep ploughing before sowing and proper crop sequences involving non-poaceous crops reduces disease intensity.
- Spot drench with Copper oxychloride at 0.25 per cent for prevent spread of disease.
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Source of hyphal segement: Plant Pathology by George N.Agrios
Content Validator: Dr. T.Raguchandar, Professor (Plant Pathology), TNAU, Coimbatore-641003
Thanks to Dr.M.N.Budhar, Professor and Head, Regional Research Station, Paiyur- 65112 |
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