These diseases are transmitted on the surface of healthy seed by spores spread from diseased heads. With common bunt winter wheat may also be infected by soil-borne spores.
Covered smut in barley
Loss in yield is directly related to the percentage of diseased tilers. In addition there can be loss in quality with downgrading of smutty grain.
Common bunt of wheat is not easily visible in the field, but the bunt balls which form instead of kernels thresh out in the grain. Broken bunt balls release masses of black powdery spores along with a fishy odor. Oat smuts and covered smut of barley stunt plants and the more compacted heads show blackened kernels and deformed awns. At harvest, black powdery spores and parts of smutted heads are mixed in the grain. Use resistant varieties or disease free seed. There are no standards for pedigreed seed. Treat seed with a fungicide if smut is observed in a seed crop or if the variety has poor resistance.
