Finger Millet 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.
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.
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 preventing spread of disease.
Source-
- TamilNadu Agritech Portal
