False Smut: Ustilaginoidea virens (Cke.) Takahashi

(Deuteromycotina: Moniliales: Dematiauae)

Local name: Kadige Roga

False smut is a fungal disease and is more severe in the years of high rainfall. The farmers consider its incidence as an omen of Good Harvest.

Period of occurrence  : Panicle emergence

Extent of yield loss    : Negligible, Udupi district 23% and DWR 3%

• 1000 grain weight by 48%
• Chaffyness by 40%
• Seedling growth
• Seed germination by 25%

Conditions favorable for the pathogen:

• Low temperature (20°C)
• High relative humidity (>92%)
• Moderate rainfall with intermittent clear and drizzling weather during flowering.
• More prevalent in seasons favorable for good growth and high yields

Host pants: Grasses and Wild rice

Damage symptoms:

• In one panicle, only few seeds showing the disease symptoms.
• Individual grains of the panicle are transformed into yellow or greenish velvety spore balls.
• These spore balls contain white mycelium and conidia.

                                            

                                             False smut affected ear head

Management

• Use disease free seeds for sowing.
• Hot water treatment of seeds at 52°C for 10 min.
• Removal and destruction of diseased panicles in field.
• Seed treatment with carbendazim 2.0g/kg of seeds.