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ŠUMARSKI LIST 13/2011 str. 131     <-- 131 -->        PDF

B. Liović: UTJECAJ PEPELNICE (Microsphaera alphitoides Griff. et Maubl.) NARAST I PREŽIVLJENJE ... Šumarski list – Posebni broj (2011), 122-129


toides Griff et Maubl., (Protection of oak new Selochnik,N., N., 1996: Effects of powdery mildew


grovth from fungi Microsphaera alphitoides and fungicides on oak seedlings. Lesnoe-Kho-


Griff et Maubl.). Rad. Šumar. inst. 33(1): 83–93.
zyaistvo , No. 6, 51–53.


Jastrebarsko.


Shirnina,L.,V., 1992:The biological effect of sisteOstrogović,
M.Z., K.Sever, I.Anić,2010: Utje


mic fungicides in the control of oak powdery
caj svjetla na prirodno pomlađivanje hrasta luž


mildew. Lesnoe –Khozyaistvo. No. 1, 48–49.
njaka (Quercus roburL.) u Park šumi Maksimir


Steinhau, Z,M., 1910: Medljika hrasta., (Oak hone-


u Zagrebu, (Influence of Light on Natural Rege


ydew). Šumarski list br. 1, 23–24. Zagreb.


neration of Pedunculate Oak (Quercus robur L.)
in the Maksimir Forest Park in Zagreb).Šumar-
Izvješće Dijagnozno – Prognozne službe, (Diagnostic-
ski list br. 3–4, 115–123., Zagreb. prognostic service report). Šumarski Institut Jastrebarsko,
2005.


Petračić,A., 1909: Oidium na hrastovim šumama.
(Oidium on oak forest)., Šumarski list, 12,
URL:http://www.indexfungorum.org/names/names.asp
441–445. Zagreb. (10. 3. 2011).


SUMMARY: Powdery mildew as plant disease caused by the fungus species
Microsphaera alphitoidesGriff et Maubl., has major impact in process of oak trees dieback.
Most threatened are seedlings and saplings. Experiences from professionals in last
few decades proved that within the habitat of Pedunculate oak, powdery mildew is one of
important factors that affects survival rate of oak’s saplings, therefore rejuvenation of
oak forests. Although fungus highly pathogenic, the researches of its influence on development
and dieback of saplings in order to justify the investments in protection are relatively
few. The researches targeted to determine the level of dependence between the
height increment and diameter increment in relation with the survival rate of seedlings
and the intensity of contamination caused by mildew, are set on research plots according
to the block distribution in fenced surfaces, under the Forest District Bjelovar of the
Croatian Forests Ltd. The experiment is set on the same model also in the Croatian Forest
Research Institute’s nursery. The acorns collected were treated with fungicides and
sawn in rows in fenced surface. In experiment two variants were tested in four repetitions;
seedlings treated with anti-mildew fungicides and seedlings without any protection.
After germination in one-month intervals the plots were cleaned from weed and the
height increment was measured, whilst based on the surface of leaves covered with mycelia
the infection caused by powdery mildew was estimated on 50 leaves sample in every
plot. Fungicides were applied every 15–20 days depending of weather conditions. For
the protection three fungicides were used: Artea 330 EC (0.5 l / ha), Anvil 5 SC (0.5 l /ha)
and Punch 10EW (0.3 l / ha) all with 250 l/ha of water and 0.2 % Sandovit surfactant.
Fungicides were used in forest nurseries seven times and five times in forest. The intensity
of photosynthesis was measured on infected and non-infected leaves with portable
gas-exchange system Li-Cor LI- 6400. On seedlings treated with fungicides at 10.00
hours was measured 8,31 µmol of CO2m-2s-1while at 14.00 hours was measured 6,76
CO2m-2s-1. On infected seedlings at 10.00 hours was measured significantly lesser value
5,38 µmol of CO2m-2s-1while at 14.00 hours 3,75 CO2m-2s-1. The research results show
the direct relationship between the infestation by powdery mildew and the intensity of
photosynthesis with the height increment and the survival rate of seedlings. This relationship
is particularly denoted inside the forest, under the canopy where average height
of seedlings (Graf 4) is significantly lesser at the infected seedlings (22,62 cm) compared
with the seedlings treated by fungicides (25,57 cm). At the infected seedlings appeared
massive defoliation 12 days earlier than at the uninfected. The survival rate of infected
seedlings (Graf 7) in the forest at the end of the 1st year is 78 % while the survival of treated
seedlings is 94 %. In opposition inside the nursery (Graf 5) the infected plants have
average height of 24,82 cm at the end of first vegetation, while treated are relatively
smaller 22,56 cm. The survival rate in the nursery (Graf 6) is approximately equal in
both treatments, at the infected seedlings 92 % comparing to 95,5 % at the uninfected.


Key words:oak seedlings, powdery mildew (Microsphaera alphitoides Griff. et
Maubl.), fungicides, photosynthesis intensity, survival rate, height increment