Uncinula necator (Schow) Burr., the Causal Agent of Grape Powdery Mildew: Economic Impact, Epidemiology and Control
Uncinula necator (Schow) Burr., prouzrokovač pepelnice vinove loze: značaj, osobine i mogućnosti suzbijanja
Author
Miladinovic, Zoran
Vuksa, Petar
Miletic, Novica
Keywords
Uncinula necatorGrape
Powdery mildew
Epidemiology
Control
pepelnica vinove loze
značaj
epidemiologija
suzbijanje
Metadata
Show full item recordAbstract
The article is an overview of what we know at present about the patogen Uncinula
necator and the disease powdery mildew of grapevine, i.e. its economic status, inoculum
source, microclimate conditions, vine susceptibility and principles of its protection.
Powdery mildew is a major grapevine disease in terms of losses. It infects the plant’s
green parts, reducing its fertility, spoiling the quality of grapes and wine and ruining plant
vitality. The process additionally affects subsequent vegetation seasons. The disease occurs
every year and its intensity depends on a number of factors.
It had long been assumed that overwintering mycelium was the primary source of
inoculum. More recent research, however, has revealed a crucial role of cleistothecia in
many vineyards. They were found in our vine-growing regions long ago but their true role
in the epidemiology of disease has been explained only recently.
Microclimate conditions considerably affect the abundance and vitality of cleistothecia
and the pathogen’s infection potential. Outbreaks and intensity of disease both depend
on them, while vine susceptibility plays another important role, depending on cultivar
and plant ontogenesis. Grapevine is most sensitive during flowering and bunch formation
when conditions are generally good for the disease to appear and spread.
Temperature, precipitation and relative air humidity may limit the occurrence of powdery
mildew, but extreme values in that respect are a rarity. Their normal scope is more or
less favourable for the disease, especially in Podgorica vineyards.
Knowing the pathogen, especially its infection potential, environmental conditions,
dynamics of host development and timely and good quality protection of vines, both preventive
and chemical, is crucial for grapevine protection.
Prevention is important but treatments with fungicides are crucial for U. necator control,
and they can either focus on destroying the inoculum and delaying mildew outbreaks or on
preventing primary and secondary infection and spreading of disease. Fungicides that are
normally used include some old compounds (sulphur, dinocap) as well as new ones (strobilurins
and hinolines), while inhibitors of ergoserol biosynthesis have an increasing role. Ovim radom učinjen je osvrt na prethodna saznanja o patogenu Uncinula necator
i oboljenju pepelnica vinove loze: o ekonomskom
značaju, izvoru inokuluma, mikroklimatskim
uslovima, osetljivosti vinove loze i načelima
njene zaštite. Pepelnica pripada grupi
ekonomski najznačajnijih oboljenja vinove
loze. Napada sve zelene delove biljaka i dovodi
do smanjenja rodnosti, kvaliteta grožđa i vina
i slabi vitalnost biljaka. To se odražava i na naredne vegetacione sezone. Javlja se svake
godine, a intenzitet njene pojave zavisi od niza
faktora. Dug o se smatralo da je prezimljujuća
micelija osnovni izvor inokuluma. Potom je utvrđeno da kleistotecije imaju dominantnu ulog
u u mnog im vinog orjima. U našim uslovima
su odavno utvrđene, a njihov pravi značaj
u epidemiologiji oboljenja sagledan je nedavno.
Na brojnost i vitalnost kleistotecija, odnosno
infekcioni potencijal patogena, značajno
utiču mikroklimatski uslovi. Od njih zavise
i vreme pojave i intenzitet oboljenja, kog
a uslovljava i osetljivost vinove loze, a ona je različita zavisno i od sortimenta i od ontogeneze
biljaka. Vinova loza je najosetljivija tokom cvetanja
i formiranja grozda, kada redovno postoje
uslovi za pojavu i širenje oboljenja. Temperatura,
padavine i relativna vlažnost vazduha mog
u biti ograničavajući faktori pojave pepelnice
vinove loze, ali se njihovi ekstremi vrlo
retko javljaju. Najčešće su u opseg u
manje ili veće pogodnosti za jaku
pojavu oboljenja, posebno u podgoričkom
vinogorju. U zaštiti vinove loze osnovno
je poznavanje patogena, posebno njegovog
infekcionog potencijala, uslova sredine i dinamike
razvića domaćina, kao i blagovremeno i kvalitetno
izvođenje preventivne i hemijske zaštite.
Preventivne mere zaštite imaju veliki značaj,
ali okosnicu suzbijanja U. necator čini primena
fungicida, koja može imati za cilj uništavanje inokuluma i odlaganje pojave pepelnice
i/ ili sprečavanje primarnog i sekundarnog
zaražavanja i širenja oboljenja. Spektar
fungicida koji se koriste sadrži stara,
odavno poznata jedinjenja (sumpor,
dinokap), ali i nova (strobilurini i hnolinoni), a značajnu ulogu imaju i inhibitori biosinteze ergosterola.