OBČUTLJIVOST
GLIVE Botrytis cinerea Pers.: Fr.
Snježana Topolovec Pintarić, Bogdan
Cvjetković
Department
of Plant Pathology, Faculty of Agriculture, HR-10000 Zagreb, Hrvaška
Siva plesen (Botrytis
cinerea) je ena izmed gospodarsko pomembnih bolezni vinske trte. Uporaba
fitofarmacevtskih sredstev ostaja edini način za zmanjšanje pojava sive plesni
v vinogradih. Težava povezana z njeno odpornostjo na fungicide omejuje uporabo
le-teh. Z namenom, da bi rešili problem z njeno odpornostjo, si po celem svetu
prizadevajo, da bi razvili nove aktivne snovi. Kljub temu, da nove aktivne snovi
dobro učinkujejo na B. cinerea, se
lahko zgodi, da nimajo nikakršnega učinka na do zdaj znane odporne biotipe te
glive. Njihov način delovanja pa je tak, da ne ustvarjajo novih odpornih
biotipov. Z raziskavami so bile razvite metode za testiranje občutljivosti
glive B. cinerea na fungicide. Pred
registracijo novih pripravkov je mogoče s poljskimi poskusi v populaciji glive B.
cinerea ugotoviti naravno odpornost. To so lahko prva znamenja za hiter
pojav odpornosti, če se aktivna snov pogosto uporablja. Zadnjih pet let so v
svetu razvili nekaj učinkovin, izmed katerih so bile v Hrvaški leta 1997
potrjeni pirimidil in ciprodinil iz skupine anilinopirimidinov ter fenheksamid (hidroksianilid)
v letu 1998. Do takrat so prevladovali botriticidi iz skupine dikarboksimidov,
katerih uporaba je bila zaradi rezistence omejena na dvakratno rabo v rastni
dobi. V letih 1998 in '99 smo spremljali poskuse z namenom ugotavljanja povečane
odpornosti na omenjene aktivne snovi v vinogradih, kjer so bile le-te pogosto
uporabljane, pa tudi v tistih, kjer niso bile nikoli uporabljane. Rase glive B. cinerea, ki so dedno odporne na pirimetanil, ciprodinil in
fenheksamid, so bile ugotovljene tako v vinogradih, kjer so pogosto uporabljali
te učinkovine, kot v tistih, kjer niso bile nikoli uporabljene. Toda tam kljub
temu še vedno ni nevarnosti za pojav praktične odpornosti.
The grey mould caused by Botrytis cinerea is one of the economically important grapevine
diseases. Chemical control remains the only way to reduce the incidence of grey
mould in grapevine but the problem of B.
cinerea resistance phenomena restricted the use of many fungicides. In order
to overcome the problem of resistance there are continuous world efforts to
develop new active ingredients. New ingredients, in addition to having a good
efficacy against B. cinerea shuold
enable the control of biotypes resistant to existing fungicides and have such a
mode of action that does not
selects new resistant biotypes.
Within such research, methods are being developed for testing the sensitivity of
B. cinerea. By performing tests in
field trials during the pre-registration phase of new fungicide it is possible
in B. cinerea populations to detect
inherently resistance. These can be signs for the rapid appearance of resistance
if the active ingredient were to be applied intensively. During the last 5 years
new active ingredients have been developed in the world, of which pyrimethanil
and cyprodinil from anilinopyrimidine group were acknowledged in Croatia in
1997, and fenhexamide (hydroxianilide) in 1998. Until then the dominant
botryticides was dicarboximides, the use of which is limited to twice during
vegetation due to resistance. In 1998 and ’99 we conducted trials in order to
monitor the risk of B. cinerea
resistance build up to the mentioned ingredients in vineyards in which those
ingredients had been applied intensively, but also in vineyards in which they
had never been used. Strains of B. cinerea
that are inherently resistant to pyrimethanil, cyprodinil and fenhexamide were
determined both in vineyards with the performed intensive control and in
vineyards in which these ingredients had never been applied, but there is still
no danger of the appearance of practical resistance.