Isolates and fungal cultures.
Race 5 isolate Alg. 3-24 of P. tritici-repentis used in this investigation
is a laboratory stock that was previously collected
from Algeria (Lamari et al. 1995). Cultures of this isolate
were grown on V8 potato dextrose agar (Lamari and Bernier
1989a) until they were 4 to 5 cm in diameter. Five plugs (1 cm
in diameter) were cut from each colony and transferred to 1-
liter Roux bottles, each containing 250 ml of Fries medium
amended with 0.1% yeast extract (Dhingra and Sinclair 1986).
The cultures were incubated without agitation at 20°C for 21
days. The filtrates were removed from the mycelial mat by
filtering through Whatman No. 1 filter paper and 0.45-μm
cellulose nitrate filters. Culture filtrates were freeze dried and
stored at –20°C until processed.