Gibellina cerealis, an unusual pathogen of wheat

The numbers of wheat plants infected by Gibellina cerealis in a long-term wheat and fallow experiment were recorded annually from 1935 to 1978. Infected plants were few in number and generally widely separated. Overall, there were about twice as many infected plants after 3 years of fallow as after 1 year. In an outside pot experiment, using soil amended with infected straw, wheat plants infected with G. cerealis, although rare, were more frequent after 4 or 5 years of fallow than after 1–3 years of fallow or continuous wheat. Similar lesions developed on wheat, barley, rye and triticale inoculated with G. cerealis, but not on oats or grass. Lesions developed on wheat grown in pots of compost inoculated with naturally infected straw collected a few months earlier, but not in pots with infected straw collected a year or more previously.