The content of ergot alkaloids (ergovaline and chanoclavine), and their pro
duction in October 1996 and during the period May-September 1997, were inve
stigated in seventeen ecotypes of perennial ryegrass (Lolium perenne L.) an
d in nineteen ecotypes of meadow fescue (Festuca pratensis Huds.), naturall
y infected with Neotyphodium spp. The ecotypes were collected in the north-
eastern part of the Czech Republic. In 1996 the content of ergovaline in th
e ecotypes of perennial ryegrass ranged from 0.00 to 2.73 mu g g(-1) dry ma
tter (DM) (one cut), and in 1997 from 0.00 to 4.65 mu g g(-1) DM (five cuts
). In meadow fescue the content of ergovaline varied from 0.00 to 0.61 mu g
g(-1) DM (one cut) in 1996, and in 1997 from 0.00 to 2.31 mu g g(-1) DM (f
ive cuts). The content of chanoclavine (investigated in 1997 in four cuts o
nly) in perennial ryegrass ranged between 0.00 and 3.39 mu g g(-1) DM, and
in meadow fescue between 0.00 and 2.26 mu g g(-1) DM. Most ecotypes of L. p
erenne reacted to the high temperature and heavy rainfall in June and July
of 1997 with an enhanced production of ergovaline, whereas the content of c
hanoclavine was not changed. Such reaction to stress conditions was not obs
erved in the ecotypes of F. pratensis. Large differences in the production
of both ergot alkaloids between different ecotypes of both plant species we
re observed.