201Fig. 7.2 ( a ) Normal Bromus tectorum infl orescence ( right ) and diseased infl orescence infected
with Tilletia bromi ( left ), ( b ) Final germination percentages after 5 weeks on PDA for a repre-
sentative T. bromi teliospore collection tested at three incubation temperatures when recently
harvested and after 8 wks of dry storage at 20 and 30 °C, ( c ) Cyclic changes in T. bromi telio-
spore germination percentage at an incubation temperature of 2 °C during time in storage for 90
wks at constant temperatures of 20 and 30 °C. (No data are available for the period 30–90 weeks
but the 90-wk data point is provided to show that at least one more cycle of dormancy release
ensued. For ( b ) and ( c ), each data point represents proportion of teliospores germinated out of
100 examined, corrected for viability; the data points are independent. Each experiment was
repeated in time for a different spore lot with similar results)
7 Community Ecology of Fungal Pathogens on Bromus tectorum