Differences between dwarf bunt and bunt diseases in cereals

In many ways, bunt and dwarf bunt are similar. However, there are several major differences between these related seedborne/soilborne cereal diseases.

• Dwarf bunt is caused by Tilletia controversa, bunt is caused by Tilletia tritici
• Dwarf bunt affects wheat, barley, rye and triticale. Bunt only affects wheat
• Unlike bunt, dwarf bunt is not yet known in the UK – it occurs in Canada, North and South America, and many parts of Europe and Asia
• Dwarf bunt can survive for relatively long periods in the soil. In the soil, free spores may remain viable in for at least 3 years, while bunt balls can survive for up to 10 years
• Plants affected by dwarf bunt are more severely stunted (to between one-quarter and one-half of their normal height)
• Infected ears tend to have a more ragged appearance than with bunt
• Normally, bunt infects the plant via the coleoptile as the seedling is emerging. However, dwarf bunt has a relatively long incubation period and often infects plants much later

Note: Seed treatments commonly used in the UK are likely to be effective against dwarf bunt.