Karnal bunt of wheat
Causal Organism:   Neovossia indica
Description It is also known as 'Partial Bunt'. Normally the disease appears sporadically but under epidemic conditions, it may cause substantial yield losses. The fungus affects the grain partially. The affected part of the grain is converted into a mass of black bunt spores while the remaining parts are normal. Freshly harvested grains emit foul smell due to the production of tri-methyl amine. Karnal bunt is both soil and air borne disease. Karnal bunt is a disease of quarantine importance because its occurrence is not known in most of the wheat growing countries of the world.
Symptoms Karnal bunt symptoms are evident when the grains have developed. After harvest, diseased grains can be easily detected by visual inspection. The grains are partially bunted. Black coloured spore mass replaces a portion of the grain and the pericarp may be intact or ruptured. Black powdery mass of spores can be seen in the groove of wheat grain. Diseased grains give off a foul fishy odour when crushed. It is due to the presence of trimethylamine in the diseased grains.
Control measure Sowing crops at night time. Seed should be treated with Vitavax at the rate of 2.5g/kg of seed Avoid excess irrigation at flowering time Spraying of Indofil [email protected]/ha in 1000 litres of water at the time of ear emergence stage. Spray of Propiconzole(Tilt [email protected]%) should be given at the time of anthesis.Integration of one spray of bio agent fungus, Trichoderma viride (0.4% suspension) give almost cent percent disease control.