Foot Rot or Bakanae Disease
By : Sanjay Naithani
 This disease has assumed immense importance in last few years, as the area under fine scented varieties like PUSA 1121 has increased considerably. The symptoms of the disease are:
• Seedlings with bakanae emerge rapidly and show abnormal elongation of plants in nursery and field.
• The infected are thin, pale in appearance with yellowish green leaves
• Reduced tillering and drying of leaves at late infection - dying of seedlings at early tillering stage
• Infected plants show tall tillers with pale-green flag leaves that rise well above healthy plants
• Partially filled grains, sterile, or empty grains for surviving plant at maturity
The disease is caused by a fungus Gibberella fujikuroi a fungus primarily transmitted through seed. Airborne spores can contaminate the panicle from heading to maturity, especially in rainy periods. The production of conidia (spores) on diseased culms coincides with flowering and maturation. The pathogen may be also soil-borne in some cases.
Conditions favouring development of disease are:
• Soil temperature of 35ºC is most favorable for infection.
• High doses of nitrogenous fertilizers.
• High temperature, ranging from 30 to 35ºC.
• Use of uncertified / untreated seeds
• Poor field sanitation.
The disease may be managed by:
• Using clean certified healthy seed.
• Infected seeds are light in weight and would float if put in 1% brine (salt solution 1Kg in 100 litres of water).
• Seed treatment with Carbendazim or Benomyl at 2-2.5gm per Kg seed.
• Spray TKS- Cona (Hexaconazole)@300ml per acre or TKS Zimba @ 300gm per acre for arresting spread.
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