FIGURE 1.

Symptom scoring, from left to right 1–9; 1-asymptomatic, 2-very weak growth reduction, normal tillering; 3-weak growth reduction, normal tillering, marked yellowing of the leaf tips (not shown); 4-weak growth reduction, reduced number of ears; 5-significant reduction in growth, reduced number of tillers and spike-bearing stalks; 6- weak growth reduction, greatly reduced number of shoots and ears; 7-plant with one to four shoots, no ears or ears stuck in the bract, strongly dwarfed; 8-plant without shoots, no spikes, heavily dwarfed; 9-plant dead.