The 411 on Ergot

From Amanda Homans, Agronomist for Decisive Farming.

In some of my field scouting lately, I have noticed that there is a higher than normal amount of Ergot in the area, in particular wheat fields.  Ergot infects both cereals and grasses; the most susceptible is rye, triticale, wheat and barley respectively.

This disease overwinters as black-grain sized fungal bodies, and in late spring, these ergots germinate and form tiny spore producing, mushroom-like structures.  These spores can be carried by wind, rain and insects. Earlier in the season, before the ergots are produced, an amber liquid or honeydew can be detected on individual flower heads.  This sticky liquid contains large amounts of the ergot spores.  Cool, damp weather in late spring and early summer favor ergot germination.

Ergot is easily recognized by the hard black bodies that replace the grains of the affected head. Heads may contain one or more ergots. Ergot bodies are highly poisonous and extremely toxic to humans and livestock.  There is also economic loss resulting in a reduction of yield and through rejection or downgrading of contaminated grain by the elevator.  Cereal spikes containing ergot have fewer kernels per head with less weight per seed.

The presence of ergot in wheat and barley in Alberta has been strongly correlated with soils that are low in copper, or with management practices that cause a copper deficiency in cereals. Wheat, and barley, grown on copper deficient soils have a high rate of pollen sterility. Barley and wheat are self-pollinating and the florets normally do not open. If the pollen is sterile, florets of wheat and barley open and expose the stigmas to ergot infection.

Some management and control of ergot include testing your soil for copper availability, crop rotation, burring of crop residue and mowing for headland grasses before seed setting.  Ergots rarely survive more than a year in the soil.  Delaying of swathing may also be a control method, as the ergots can be shaken out of the heads in windy weather.  If you are intending to use the grain for seed, it is best to store the ergoty grain for two (2) years because the ergots will die, and the grain will remain viable for many more years.