KAU Agri Infotech Portal

Rice (Oryza sativa)

The fungus that causes the disease can live in the soil for many years.
Sometimes it will be a light green, grayish spot, like a burn from boiling water.
The initial symptoms are formed in the lower leaf sheaths as circular to oblong grey green, water soaked spots at the base of the culms near water level in low land and at ground level in upland rice.
Under favourable conditions, the infection spreads rapidly, vertically up and horizontally between tillers.
As the lesions mature, they become straw coloured with dark brown margin and irregular in outline.
Under moist conditions, cobweb- like white mycelia are produced on lesions, which give rise to white pinhead like sclerotial initials at first, which turn brown on maturity.These sclerotia are easily dislodged from the plant.
The disease progress is rapid at maximum tillering stage.The disease may also progress to flag leaf and panicle which will prevent the normal emergence and expansion of ears and result in poor filling of grains.
Field symptom is characterized by the formation of circular dried patches. This will progress with increased disease severity.

Use tolerant varieties such as Kairali, Kanchana, Aiswarya, Athira, IR-8, Nila etc.
Remove weeds, infected stubbles and crop residues to reduce inoculum. Thermosanitation by burning straw and stubbles in the field to destroy the inoculum.
Deep ploughing and flooding for four weeks before transplanting.
Follow optimum spacing to avoid dense crop stand.
Avoid over use of nitrogenous fertilizers.
Apply organic amendments viz., neem cake @ 150 kg / ha or FYM 12.5 tones / ha.
Avoid flow of irrigation water from infected fields to healthy fields

Sl.No	Generic Name	Trade Name	Color code	Dosage/litre	Knapsack Sprayer (Capacity 10L)	Dosage/acre (200 L)	Dosage/hectare (500 L)	Remarks
1	Carbendazim 50 WP	Bavistin, Benfil, Bengard, Benlate, Benmain, Bensaan, Carben, Carziim50, Dhanustin, Dhanustin 50 WP, Fungiguard, Gancarzin50, Glizim, Mintho, Tagstin, Tiara, Zoom	Green	1 g/ litre of water	10 g	200 g	500 g	Spray on rotation as and when disease is noticed.
2	Propicanozole 25 EC	Bumper, Dhan, Pinade, Propiguard, Propik Final, Radar, Result, Tilt, Tilt Albu, Zetox	Blue	1 ml/ litre of water	10 ml	200 ml	500 ml	Spray on rotation as and when disease is noticed.
3	Hexaconazole 5 EC	Alert Creeper, Contaf, Corazole, Danzole, Force 5C, Hexaan, Hexacone, Hexadhan, Hexamax, Hexan, Hexazole, Mainex EC, Sitara, Strike, Titan, Topper, Topper plus EC, Xantho	Blue	1 ml/ litre of water	10 ml	200 ml	500 ml	Spray on rotation as and when disease is noticed.
4	Tebuconazole 25.9 EC	Folicur, Orius, Tebustar	Blue	1-1.5 ml/ litre of water	10 - 15 ml	200 - 300 ml	500- 750 ml	Spray on rotation as and when disease is noticed.
5	Trifloxystrobin + Tebuconazole 75 WG	Nativo	Blue	0.5 g/ litre of water	5 g	100 g	250 g	Spray on rotation as and when disease is noticed.
6	Carpropamid 27.8 SE	Arcado, Protega	Green	1 ml/ litre of water	10 ml	200 ml	500 ml	Spray on rotation as and when disease is noticed.