FOLIA BIOLOGICA ET GEOLOGICA 52/1-2, 5–26, LJUBLJANA 2011
ABSTRACT UDC 630*23:582.632.2(497.4Pohorje)
 575.2:582.632.2(497.4Pohorje)
Genetic variability and suitability of under-planted beech 
in selected N o rwa y sp ruce mo nocul tures o n the P oho rje 
massif 
In order to investigate the genetic variability of under-
planted young beech in Norway spruce monocultures, 100 
randomly chosen individuals on the research plots Brička and 
Kladje were analysed by means of isozyme gene markers at 17 
polymorphic gene loci. The single locus mean value of the 
Gregorius (1974) allelic distance between the sample popula-
tions was relatively high (d
0
 = 9.6 %). The results do not sup-
port the hypothesis of a common origin of the planting mate-
rial from a single ancestral population. A proposal is made for 
an extension of the network of forest beech seed stands for 
future melioration of spruce monocultures on Pohorje.
Key words: conversion of spruce monoculture, Fagus syl-
vatica (L.), artificial regeneration, isoenzyme, genetic varia-
tion, forest site, seed stand, Slovenia
GENETIC V ARIABILITY AND SUITABILITY OF UNDER-PLANTED 
BEECH IN SELECTED NORWAY SPRUCE MONOCULTURES ON 
THE POHORJE MASSIF 
GENETSKA V ARIABILNOST IN PRIMERNOST PODSAJENE BUKVE 
V IZBRANIH SMREKOVIH MONOKULTURAH NA POHORJU
Gregor BOŽIČ
1
, Lado KUTNAR
2
 & Mitja ZUPANČIČ
3
IZVLEČEK UDK 630*23:582.632.2(497.4Pohorje)
 575.2:582.632.2(497.4Pohorje)
Genetska variabilnost in primernost podsajene bukve v iz-
branih smrekovih monokulturah na Pohorju
Za raziskavo genetske variabilnosti podsajenih mladih 
bukev v smrekovih monokulturah na Pohorju smo analizirali 
100 naključno izbranih osebkov na raziskovanih ploskvah 
Brička in Kladje. Uporabili smo metodo analize izoencimskih 
genskih označevalcev. Genetsko variabilnost smo ocenili na 
17 polimorfnih genskih lokusih. Genetska razdalja (d
0
) med 
vzorčenima populacijama izračunana po Gregorius (1974) je 
sorazmerno velika in znaša 9,6 %. Rezultati raziskave ne pod-
pirajo hipoteze o skupnem izvoru saditvenega materiala iz 
enotne predniške populacije. Podan je predlog za razširitev 
mreže gozdnih semenskih objektov bukve za potrebe premene 
smrekovih monokultur na Pohorju.
Ključne besede: premena smrekove monokulture, Fagus 
sylvatica (L.), umetna obnova, izoencim, genetska variabil-
nost, gozdno rastišče, semenski sestoj, Slovenija
 1 
Dr. Gregor Božič, Department of Forest Physiology and Genetics, Slovenian Forestry Institute, Večna pot 2, 1000 Ljubljana, 
gregor.bozic@gozdis.si
 2 
Dr. Lado Kutnar, Department of Forest Ecology, Slovenian Forestry Institute, Večna pot 2, 1000 Ljubljana, lado.kutnar@gozdis.si
 3 
Dr. Mitja Zupančič, Slovenian Academy of Science and Arts, Novi trg 5, 1000 Ljubljana
Folia biologica et geologica · Volume / Letnik 52 · Number / Številka 1 
· 2011

6
G. BOŽIČ, L. KUTNAR & M. ZUPANČIČ: GENETIC VARIABILITY AND SUITABILITY OF UNDER-PLANTED BEECH IN SELECTED ...
FOLIA BIOLOGICA ET GEOLOGICA 52/1-2 – 2011
At the beginning of the nineties, storm damage and a 
gradual increase in bark beetles reduced the stability of 
Norway spruce stands in Europe and caused a percepti-
ble reduction in vitality, which was observed until the 
end of the last decade. The forestry profession endeav-
oured to find a method of increasing the long term sta-
bility and preserving the permanence of these stands, 
which led to the choice of habitats of the most suitable 
tree species. Because of dubious management methods 
and public pressure and the demand for increased sus-
tainability, the insertion of under-planted deciduous 
trees in coniferous forests became a widely established 
silvicultural method in Europe. The silvicultural 
grounds for such a transformation were relatively poorly 
defined.
 In the second half of the last century, the conver-
sion of pure spruce stands (Picea abies L. Karst.) was one 
of the main forest-silviculture challenges in Europe 
(Zerbe 2002;  Teuffel, Heinrich & M. Baumgarten 
2004). It is thought that there are at least 6 to 7 million 
hectares of pure spruce stands outside their natural hab-
itats in Europe, of which 4-5 million hectares are estab-
lished on sites on which deciduous or mixed deciduous-
coniferous forests should predominate. The current 
state is the result of forest management decisions in the 
past, when mixed stands were exposed to agricultural 
exploitation, littering, grazing and obtaining firewood 
(Johann et al. 2004). The great need for timber brought 
about by industrialisation led to an acceleration of mo-
nocultures of fast growing trees. In the last 200 years, 
spruce was most often chosen as the tree species for ar-
tificial renewal of stands because of its fast growth, the 
simple establishment of stands, low requirements in re-
lation to thinning and because it was not excessively 
burdened by grazing game.
The introduction of spruce outside its natural area 
of distribution is linked to numerous, for the most part 
short-term benefits. The species is economically very in-
teresting, having the potential to produce high quality 
timber in a short time span. European deciduous forests 
in the past covered larger areas than they do today, so 
the general opinion is held in Europe that planning de-
ciduous stands is a step towards sustainable forestry 
(Hannah, Carr & Lankerani 1995; Stanturf & 
Madsen 2002). One of the ways of establishing them is 
to change spruce into deciduous or mixed forest. The 
transformation of the widespread homogeneous spruce 
into natural deciduous forests has been used in forestry 
practice in Europe for the last fifty years.
A number of factors argue in favour of the trans-
formation. Spruce has been shown to be unstable in 
many cases, it is exposed to a reduction of vitality, 
storm damage, attacks of bark beetles, drought and it 
has a negative impact on the soil (Larsen 1995). Ap-
preciable changes in the environment and landscape, 
with consequential changes or reduction of biotic di-
versity (Grabherr & Koch 1993) have made public 
opinion less favourable. Climate change, and especially 
the increasing likelihood of the occurrence of climatic 
extremes, such as storms, have exposed the vulnerabil-
ity of spruce monocultures and stress the need for re-
ducing the risk by including other tree species in spruce 
stands (Bradshaw et al. 2001). The increase in the 
price of deciduous timber has reduced the economic 
justification of planning anthropogenic coniferous 
stands (Abildtrup, Riis & Jellesmark-Thorsen 1997; 
Spiecker 2000).
F o r s u c c e s s f u l m e l i o r a t i o n , u n d e r - p l a n t i n g w i t h 
beech (Fagus sylvatica L.), either below the shade of the 
parent stand or in gaps is a possible alternative to a clear-
cut method of management, which is still used in Eu-
rope. Under-planting is an old silvicultural technique, 
which is receiving renewed attention today (Otto 1986; 
Spellmann & Wagner 1993). The advantages of under-
planting are fewer weeds, a more favourable micro-cli-
mate, protection from winter frosts (Löf 2000), as well 
as a more favourable attitude of the public, in contrast to 
clearcut (Mattsson & Li 1994). 
In Slovenia, conversion of pure spruce into mixed 
stands began in the mid-20th century. Although forests 
in Slovenia are relatively well-preserved in comparison 
to Central Europe, because of the heritage of the past, 
the present tree composition of forests deviates from 
what is considered natural (Diaci &  Grecs 2003). The 
share of spruce in timber stocks is 32 %, while the esti-
mated natural share is approximately 8 %. Slovenia is a 
country of deciduous, mainly beech forests (Šercelj 
1996, Ž. Košir et al. 1974, Dakskobler 2008). Seventy 
percent of forests in Slovenia are classified into forest 
communities in which beech is the leading species.
The period of active melioration of spruce stands 
started in the early 50s with an instruction from the 
Ministry of Forestry that a campaign should be started 
for the planting of noble deciduous trees in spruce plan-
tations, mainly sycamore maple (Acer pseudoplatanus) 
(Diaci 2006). Efforts were not for the most part success-
ful because of too high a density of large herbivores 
(Diaci 2006, summarised from oral sources Mlinšek 
2004). The success of realising the first regulatory plans 
after the Second World War were essentially more suc-
cessful. In 1954, Mlinšek elaborated an extensive regula-
tory plan for the Mislinja forest-management unit, 
1. INTRODUCTION

7
G. BOŽIČ, L. KUTNAR & M. ZUPANČIČ: GENETIC VARIABILITY AND SUITABILITY OF UNDER-PLANTED BEECH IN SELECTED ...
FOLIA BIOLOGICA ET GEOLOGICA 52/1-2 – 2011
which mainly embraced spruce plantations (Mlinšek 
1955). It began with gradual conversion on the basis of a 
control method, with detailed analysis of increment, se-
lective thinning was introduced and increased inspec-
tion. He introduced an overall methodology of under-
planting spruce plantations with seedings and pullings 
of beech (seedlings pulled from natural forest regenera-
tion in a forest stand) and individual and group protec-
tion against grazing, ensured an adapted approach to 
sites. Various methods of individual protection were 
tried and considerable success was achieved with ce-
ment mortar. Because of a lack of seed trees of beech and 
seedings, pullings of beech were transferred from more 
or less suitable sites on the north side of Pohorje (Diaci 
2006).
In order to evaluate the genetic variability of the 
under-planted beech in pure spruce stands on Pohorje, 
we performed genotype analysis in the juvenile devel-
opment stage of beech of test populations, using iso-
zymes. The purpose of the study was to assess the level 
of genetic relationship of populations of under-planted 
beech by the method of isozymes gene markers. W e 
wished to test the hypothesis that the sampled popula-
tions of beech have a similar genetic structure and do 
not show major deviation from average value parame-
ters. The study is intended to contribute to a more de-
tailed understanding of genetic structures, genetic di-
versity and genetic differentiation of beech populations 
that have been introduced into spruce monocultures 
on Pohorje.   
2. STUDY AREA
Pohorje is a distinctive mountain plateau, lying at an 
altitude of 1200-1500 m and is an extension of the Cen-
tral Alps. The massif is constructed of metamorphic 
and magmatic rocks and sediments (Budnar- T regubov 
1958). The climate is medium mountain. In the last 
4000 to 5000 years, various forms of fir beech forests 
with a modest share of spruce have predominated in 
primary forests (Culiberg & Šercelj 2000). The origi-
nal forests on Pohorje consisted mainly of beech, fir 
and spruce, which larch interspersed in places 
(Breznikar et al. 2006). Natural spruce forests are 
edaphically conditioned and thus limited to swampy 
level areas, bowl-shaped dips and gently inclined slopes 
on the Pohorje plateau. In the last two centuries, the 
tree composition of Pohorje forests has changed. Today, 
anthropogenically altered spruce stands predominate. 
Because of the negative influences of the tree composi-
tion, the sustainable yield from the forests is also threat-
ened (Breznikar et al. 2006). In the past, in the period 
from 1800 to the end of the Second World War, because 
of the influence of the German school of forest manage-
ment and its agricultural principles, spruce was inten-
sively introduced in the Pohorje forests and the renewal 
of forests was directed towards establishing pure spruce 
stands. After the Second World War, this silvicultural 
principle was gradually abandoned. Anthropogenic 
spruce stands on Pohorje, among which belong stand 
constructions with a predominant share of spruce on 
beech and fir habitats, today cover 27.000 ha or 45 % of 
t h e t o t al f o r e s t a r e a o n P o h o r j e ( B r e z n i k a r e t al . 
2006).
The negative effects of the altered tree composition 
dictate a search for forest management-actions by which 
a more natural intermixture of tree species in forest 
stands will be introduced. Because of the negative im-
pact of encouraging spruce on beech and fir sites, plan-
ning measures in spruce monocultures requires an un-
derstanding of the processes of degradation of sites. 
With a predominant share of spruce in stands, raw 
humus begins to accumulate in the soil and the lability 
of the soil also contributes to its damaging action. 
Spruce, because of its shallow roots, over-exploits the 
upper soil horizons, and the lower horizons begin to 
compact. A worsening of the physical properties of the 
soil occurs (reduction of aeration) and the acidity of the 
soil increases, the availability of nutrients is reduced and 
the intensity of humification and mineralisation of or-
ganic substances in the soil is reduced, initiating the ac-
cumulation of unfavourable forms of humus. With the 
gradual compaction of the soil profile and increasing of 
the impermeable horizon the biologically active depth 
of the soil is reduced and, because of the worsened phys-
ical properties of the soil, the soil water capacity is re-
duced. Moist forms of raw humus and mosses increase 
the surface accumulation of rainwater and condition the 
process of pseudogleyification of the soil (Breznikar et 
al. 2006). 
The development of more stable forest structures 
and retarding degradation processes in forest soils are 
the main strategic aims in planning the development of 
forests on Pohorje. Planned interventions for meliora-
tion of the altered stand constructions and targeted sil-
viculture measures began in the Mislinje part of Pohorje 
in the fifties of the last century and have gradually been 
extended to the entire region of Pohorje. The main mel-
ioration measure is the introduction of broadleaf trees, 

8
G. BOŽIČ, L. KUTNAR & M. ZUPANČIČ: GENETIC VARIABILITY AND SUITABILITY OF UNDER-PLANTED BEECH IN SELECTED ...
FOLIA BIOLOGICA ET GEOLOGICA 52/1-2 – 2011
mainly beech, in spruce stands and eliminating the im-
pact of over-numerous game on young forest trees.
We chose research sites on the southern side of Po-
horje, in research plots of the Slovenian Forestry Insti-
tute, at the locations Brička above Mislinjski jarek (SFS 
District unit Slovenj Gradec) and Kladje near Osanka-
rica (SFS District unit Maribor) (Table 1). Both sites are 
presumed to have been covered with beech or fir-beech 
forests, with interspersed spruce, before the more in-
tensive interventions and degradation processes. The 
cited locations are potential natural sites of acidophil-
ous beech with white wood-rush (Luzula luzuloides), a 
geographic variant with Cardamine trifolia (Luzulo al-
bidae-Fagetum Meusel 1937 var. geogr. Cardamine tri-
folia (Marinček 1983) Marinček & Zupančič 1995). 
Relatively well preserved acidophilous beech forest still 
grows on a smallish area on the edge of the Brička site. 
The wider region of the Kladja site is considerably 
changed but, on the basis of individual remains of such 
forest, it be concluded that it is a potential site of this 
association. However, in the wider area of this part of 
Pohorje, the association of beech with Cardamine 
waldsteinii has been charted. This is a zonal associa-
tion of Pohorje high mountain beech forest, which 
grows on the upper part of the montane belt of the Po-
horje massif, i.e., at an altitude from 1000 to 1300 m. In 
addition to the characteristic tree species of beech and 
sycamore maple, fir and spruce also appear with larger 
shares in relatively well preserved stands of this asso-
ciation. On this basis, a special geographic variant of 
this association with fir was defined (Cardamini saven-
si-Fagetum Ž. Košir 1962 var. geogr. Abies alba Ž. Košir 
1979). 
Because of the promotion of spruce in the past, the 
area of the sites is overgrown with spruce monocultures. 
The starting point for the selection of research plots, in 
addition to the requirement for spruce covered potential 
beech sites, also included the presence of a larger number 
of vital under-planted trees of beech within individual 
areas, a similar age of the planted beech in comparable 
locations and possibilities of including the research plots 
within the framework of other investigations. 
Table 1: Survey of research site characteristics according to Čater (2011)
Preglednica 1: Značilnosti izbranih raziskovalnih objektov (Čater 2011)
Plot
(Ploskev)
Altitude 
(m) 
(Nadmorska 
višina)
Latitude
(Severna zem-
ljepisna širina)
Longitude 
(Vzhodna zem-
ljepisna dolžina)
Annual precipitation 
(mm) 
(Letne padavine)
Annual average air T (°C) 
(Povprečna letna temper-
atura zraka)
Dominant soil type 
(Prevladujoči talni tip)
Brička (BRI) 1093 46°28’40’’ 15°15’40’’ 1190 9.1
Dystric Cambisol 
(Distrična rjava tla)
Kladje (KLA) 1308 46°28’48’’ 15°23’24’’ 1066 9.2
Dystric Cambisol 
(Distrična rjava tla)
The research sites are overgrown by mature trees of spruce and under-planted beech in the juvenile development 
stage. At Brička above Mislinjski jarek, the area is covered by 173 spruce / ha, with an estimated growing stock of 
spruce stands of 477 m
3 
/ ha, and at Kladje near Osankarica, 126 trees/ha with a growing stock of 302 m
3 
/ ha (Čater 
2011). In 2006, the age of the sampled under-planted beech was estimated at around 10-15 years (Čater 2011). 
3. MATERIAL AND METHODS
3.1 Sampling
At the research plots Brička and Kladje on Pohorje, we 
randomly sampled 100 beech trees for genetic testing. 
On each area of a size 100 m x 100 m, we uniformly cov-
ered vital trees of under-planted beech. In the winter 
period of 2005 / 2006, we took a branch with dormant 
buds from each of the sampled trees, which we used for 
the extraction of enzymes. The buds were preserved 
until analysis in test tubes at a temperature of -20° C. 
The size of the sample was 50 trees at each site.
3.2 Analysis of isoenzymes
We investigated the genetic characteristics of the beech 
by the method of isozyme analysis. The research material 
consisted of dormant buds. The genotype of each tree 
was established by means of horizontal electrophoresis 
o n star c h g e ls. Enzym e extra cti o n fr o m th e d o rm an t 
buds, electrophoresis, staining the gels and reading the 
electrophoregrams was performed by standard method-
ological procedures for the analysis of beech samples 
(Konnert, Hussendoerfer & Dounavi 2004). The lab-

9
G. BOŽIČ, L. KUTNAR & M. ZUPANČIČ: GENETIC VARIABILITY AND SUITABILITY OF UNDER-PLANTED BEECH IN SELECTED ...
FOLIA BIOLOGICA ET GEOLOGICA 52/1-2 – 2011
oratory part of the analysis was performed in the frame-
work of the research tasks of project “Carbon dynamics 
in natural beech forests” (L4-6232) in February 2006. 
Table 2: Gene loci analysed
Preglednica 2: Analizirani genski lokusi
Enzyme system 
(Encimski system)  
E.C. Code 
(E.C. koda)
Analysed gene loci
(Analizirani genski lokusi) 
Number of alleles 
(Število alelov)
Aspartate aminotransferase (Aat) syn. Glutamate oksaloacetate transam-
inase (Got)
(Aspartat aminotransferaza syn. Glutamat oksalacetat transaminaza) 
2.6.1.1 Aat-A, Aat-B 2, 2
Aconitase (Aco)
(Akonitaza)
4.2.1.3 Aco-A, Aco-B 2, 3
Isocitrate dehydrogenase (Idh) 
(Izocitrat dehidrogenaza)
1.1.1.42 Idh-A 2
Malate dehydrogenase (Mdh) 
(Malat dehidrogenaza)
1.1.1.37 Mdh- A, Mdh-B, Mdh-C 2, 4, 2
Menionreduktase (Mnr)
(Menionreduktaza)
1.6.99.2 Mnr-A 3
Peroxidases (Per)
(Peroksidaze)
1.11.1.7 Per-A, Per-B 2, 3
Phosphoglucose isomerase (Pgi)
(Fosfoglukoza izomeraza)
5.3.1.9 Pgi-B 2
Phosphoglucomutase (Pgm) 
(Fosfoglukomutaza)
2.7.5.1 Pgm-A 2
Shikimate dehydrogenase (Skdh)
(Šikimat dehidrogenaza)
1.1.1.25 Skdh-A 3
6-Phosphogluconate dehydrogenase (6-Pgdh)
(6-Fosfoglukonat dehidrogenaza)
1.1.1.44 6-Pgdh-A, 6-Pgdh-B, 6-Pgdh-C 3, 2, 4
Total (Skupaj) 10 17 43
The laboratory work was done in the Bayerische Amt für 
forstliche Saat - und Pflanzenzucht in Teisendorf, Ger-
many, under the leadership of Dr. Monika Konnert. 
The results of isozyme analysis were evaluated by 
the relative frequency of alleles and genotypes, by indi-
vidual gene loci. The genetic structure of the population 
was described on the basis of the frequency of individual 
alleles at polymorphic loci. Any gene locus at which we 
found at least one allele was considered to be a polymor-
phic locus, irrespective of its relative frequency in the 
population (without criteria).
The frequencies of distribution of alleles at loci were 
described according to individual populations by 4 al-
lele profiles, which we defined according to Finkeldey 
(1993), as: i) fixation, if there was only 1 allele (allele fre-
quency 100 %) at an individual gene locus, ii) low level of 
polymorphism if there were frequent alleles at an indi-
vidual gene locus (allele frequency > 80 %) and one or 
more rare alleles, iii) high level of polymorphism if there 
were at least two alleles as predominant at an individual 
gene locus (allele frequency > 20 %), iv) untypical profile 
if the allele structure at an individual gene locus could 
not be classified into the first three profiles.  
We interpreted the genetic variability within indi-
vidual populations by the parameters of genetic multi-
plicity and genetic diversity. With the parameter of ge-
netic multiplicity, which takes into account only the 
number of different gene types in individual popula-
tions, we calculated three parameters: (1) share of poly-
morphicity of the analysed gene loci (P %); (2) the high-
est possible number of different alleles (M
max
); (3) the 
average number of alleles per polymorphic locus (A/L). 
With the parameter of genetic diversity, which, in con-
trast to the parameter of genetic multiplicity takes into 
account in addition to the number of different gene 
types also their frequency of appearance in a popula-
tion, we calculated observed heterozygosity (H
a
) and 
conditional heterozygosity (H
c
; Gregorius, Krau-
hausen & Mueller-Starck 1986), effective allele di-
versity (ν; Gregorius 1978, Gregorius 1987), multi-
locus hypothetical gametic diversity (ν
gam
) and the level 
of genetic differentiation among individuals within a 
population (δ
T
; Gregorius 1987), which, with larger 
samples, is the same as the share of expected heterozy-
gosity, created by random mating or panmixia (H
e
;  Nei 
1973). We used the χ2 test to check how the actual het-
erozygosity shares in under-planted young beech dif-
fered from expected heterozygosity shares created by 
random mating (Hardy-Wienberg equilibrium), which 
we carried out by loci separately for each sample popula-
tion individually, at a level of risk α = 0.05. 

10
G. BOŽIČ, L. KUTNAR & M. ZUPANČIČ: GENETIC VARIABILITY AND SUITABILITY OF UNDER-PLANTED BEECH IN SELECTED ...
FOLIA BIOLOGICA ET GEOLOGICA 52/1-2 – 2011
We gave genetic differentiation between the sam-
pled populations of under-planted beech at the sites 
Brička and Kladje by the criteria of average genetic dis-
tance (d
0
; Gregorius 1974). Statistical comparison of 
the genetic structures of the beech was carried out on 
the basis of the χ2 test of the homogeneity of allele fre-
quencies by loci. The null hypothesis of homogeneity of 
allele distributions between populations was rejected at 
the level of risk α = 0.05. For calculating individual pa-
rameters, we used the GSED programme for evaluating 
isozyme analysis data (Gillet 1998). 
4. RESULTS
The research was primarily intended to shed light from 
a genetic point of view on monocultures of spruce on 
Pohorje meliorated with under-planted beech. The aim 
was to evaluate the genetic structure of under-planted 
beech at the Brička and Kladje sites, i.e., on degraded 
potential natural sites of acidophilous beech forest with 
white wood-rush (Luzula luzuloides), the geographic 
variant with Cardamine (Luzulo albidae-Fagetum Meu-
sel 1937 var. geogr. Cardamine trifolia Marinček (1983) 
M arin če k & Z u p an či č 1 99 5 ) . W e wi s h e d t o ev al ua t e 
whether there are differences in the genetic structures 
among groups of trees of under-planted beech. The re-
sults of genetic comparison are shown in Tables 3 and 4 
for 17 polymorphic gene loci.
4.1 Allele and genotype frequencies
It is clear from the relative allele frequencies of the ana-
lysed loci (Table 3) that there is polymorphism at all 17 
analysed gene loci in the populations (P = 100 %). In 
both populations, we discovered a low level of polymor-
phism at 3 loci (Aat-A, Aco-A, Skdh-A), a high level of 
polymorphism at 2 loci (Aat-B, Per-A). Locus Idh-A also 
shows a similar polymorphism. We found untypical 
profiles in both populations at 6 loci (Aco-B, Mdh-A, 
Mnr-A, Pgi-B, 6-Pgdh-A, -B). We found a distinct transi-
tion between low and high levels of polymorphism in the 
test populations at 5 loci. Loci Per-B and 6-Pgdh-C re-
flect low polymorphism in the sample from Brička and 
high polymorphism in the sample from Kladje, while 
loci Mdh-B, -C and Pgm-A have low polymorphism in 
the sample from Kladje and high in the sample from 
Brička. The same predominant allele is always present in 
both sampled populations. The frequency of the main 
allele was found in a range of 54 % to 99 %. Frequencies 
above 10 % could additionally be achieved by alleles Aat-
B
2
, Aco-B
2
, Idh-A
2
, Mdh-A
1
, Mdh-B
4
, Mdh-C
1
, Per-A
1
, 
Per-B
1
, Pgm-A
2
, 6-Pgdh-A
4
, 6-Pgdh-B
1
 and 6-Pgdh-C
4
, 
while other alleles appeared with low frequencies. 
The allele frequencies, for example, change greatly 
with alleles Mdh-B
4
, Per-B
1
, Pgm-A
2
 and 6-Pgdh-C
4
. The 
frequencies of alleles Per-B
1
 and 6-Pgdh-C
4
 are lower in 
the sample from Brička than in the sample from Kladje 
(11 % vs. 37 % and 8 % vs. 23 %), while the allele frequen-
cies of Mdh-B
4
 and Pgm-A
2
 are higher in the sample 
from Brička than in that from Kladje (16 % vs. 5 % and 
40 % vs. 9 %). The allele variants Aat-A
1
, Mdh-B
2
, Pgi-B
3
, 
6-Pgdh-A
4
, 6-Pgdh-C
5
 are also interesting, which are 
only rarely present in the Kladje population (a frequency 
of less than 5 %) but more frequently in the Brička popu-
lation (up to 11 %) or Mdh-A
1
, which is rare in the Brička 
population (1 %) and more frequent in the population 
from Kladje (10 %). 
Comparison of the genotype frequencies indicates 
the existence of differences between the compared sam-
ple populations at individual gene loci, namely at 7 of 
the total of 17 analysed gene loci. Homozygous and het-
erozygous types that are much more frequent in the 
Brička sample than in the Kladje are: Per-B
22
 (70 % vs. 32 
%), Pgm-A
23
 (44 % vs. 18 %), Pgm-A
22
 (18 % vs. 0 %), 
Mdh-A
33
 (98 % vs. 80 %), Mnr-A
33
 (90 % vs. 74 %), 
6-Pgdh-C
15
 (20 % vs. 4 %) and Pgi-B
23
 (16 % vs. 2 %). 
Heterozygous or homozygous types much more fre-
quent in the Kladje sample than in the Brička sample 
are: Pgm-A
33
 (82 % vs. 38 %), Mdh-A
13
 (20 % vs.  2 %), 
Per-B
12
 (30 % vs. 14 %), Per-B
11
 (20 % vs. 4 %), Mnr-A
35
 
(20 % vs. 6 %) and Mdh-B
33
 (72 % vs. 54 %). 

11
G. BOŽIČ, L. KUTNAR & M. ZUPANČIČ: GENETIC VARIABILITY AND SUITABILITY OF UNDER-PLANTED BEECH IN SELECTED ...
FOLIA BIOLOGICA ET GEOLOGICA 52/1-2 – 2011
4.2 Intra-population genetic variation 
4.2.1 Genetic multiplicity
In terms of meaning, the expression genetic multiplicity 
refers exclusively to the number of genetic categories (al-
leles, genotypes) of a population or parts of it. On the 
entire study area, we discovered 43 different alleles 
(M
max
) at 17 polymorphic loci in the sample popula-
tions. We did not find all possible allele variants in ei-
ther population of under-planted beech. Total allele 
multiplicity is represented in rejuvenated groups of 
beech from 93.0 % (Brička) to 95.3 % (Kladje). Both pop-
ulations on average have the same number of alleles per 
locus present (A/L = 2.40).  
4.2.2 Genetic diversity
Genetic diversity is the variability of individuals within 
a population, which is expressed by the frequency of dif-
ferent genetic categories within the population. The cri-
terion of genetic (allele) diversity in a population is the 
actual available or effective number of alleles at an indi-
vidual locus. Because the contribution of rare alleles 
(i.e., alleles with a frequency < 5 %) to the total amount 
is small, this criterion also expresses the actual level of 
equilibrium of frequent alleles. Comparison of the avar-
age values of the effective number of alleles per locus (ν) 
indicates the diversity of the sampled populations. Val-
ues range from 1.28 (Kladje) to 1.34 (Brička), which cor-
responds to a ratio of 1:1.05. The corresponding smaller 
value of effective number of alleles per locus in the Kl-
adje sampled population, with a value of A/L = 2.40, in-
dicates the presence of a larger share of rare alleles. Val-
ues of allele diversity (ν) by individual loci are shown in 
Table 4. Analysis of the hypothetical multi-loci gametic 
diversity (ν
gam
) of the test trees showed that the number 
of genetic variants of the 17 loci gametic types that the 
group of 50 sample trees in the populations could have 
produced ranges from 99 .8 (Kladje ) to 203. 1 (Brička ) 
Table 3: Relative allele frequencies of under-planted beech populations from the Brička (BRI) and Kladje (KLA) locations on 
Pohorje presented per gene loci
Preglednica 3: Relativne alelne frekvence populacij podsajene bukve z območja Brička (BRI) in Kladje (KLA) na Pohorju s 
prikazom po lokusih
Locus  (Lokus) Alelle (Alel)
BRI
N = 50
KLA
N = 50
Locus  
(Lokus)
Alelle (Alel) 
BRI
N = 50
KLA
N = 50
Aat-A 1 0.060 0.030 Per-A 1 0.280 0.240
2 0.940 0.970 2 0.720 0.760
Aat-B 2 0.330 0.290 Per-B 1 0.110 0.370
3 0.670 0.710 2 0.830 0.540
3 0.060 0.090
Aco-A 2 0.970 0.990
3 0.030 0.010 Pgi-B 2 0.920 0.990
3 0.080 0.010
Aco-B 2 0.170 0.090
3 0.810 0.910 Pgm-A 2 0.400 0.090
4 0.020 - 3 0.600 0.910
Idh-A 2 0.180 0.160 Skdh-A 2 0.010 -
3 0.820 0.840 3 0.990 0.960
5 - 0.040
Mdh-A 1 0.010 0.100
3 0.990 0.900 6-Pgdh-A 2 0.890 0.950
3 - 0.010
Mdh-B 1 0.050 0.080 4 0.110 0.040
2 0.090 0.010
3 0.700 0.860 6-Pgdh-B 1 0.120 0.090
4 0.160 0.050 2 0.880 0.910
Mdh-C 1 0.250 0.180 6-Pgdh-C 1 0.810 0.720
2 0.750 0.820 3 0.010 0.030
4 0.080 0.230
Mnr-A 3 0.930 0.870 5 0.100 0.020
4 - 0.030
5 0.070 0.100

12
G. BOŽIČ, L. KUTNAR & M. ZUPANČIČ: GENETIC VARIABILITY AND SUITABILITY OF UNDER-PLANTED BEECH IN SELECTED ...
FOLIA BIOLOGICA ET GEOLOGICA 52/1-2 – 2011
and corresponds to a ratio of 1:2.04. Although the calcu-
lated values have only an indicative character, this com-
parison suggests greater potential of the group of under-
planted beech trees at the Brička site than that of the 
group of under-planted beech trees at the Kladje site for 
the production of genetically different gametes, which 
will be subject to genetic variation in new generations. 
The average value of actual (observed) heterozygosity 
(H
a
) for the 17 loci gene pool are in a range from 21.1 % 
in the group of trees from Kladje to 23.5 % in the Brička 
group of trees, which corresponds to a ratio of 1:1.11. 
The level of heterozygosity explicitly differs between the 
test populations from Brička and Kladje at 5 loci, name-
ly at Mdh-A (2 % vs. 20 %), Mnr-A (6 % vs. 26 %), Per-B 
(26 % vs. 48 %), Pgi-B (16 % vs. 2 %) and Pgm-A (44 % vs. 
18 %).
Table 4: Comparison of indicators of genetic varia-
bility for under-planted populations of beech at Brička 
(BRI) and Kladje (KLA): number of alleles per locus 
(A/L), allelic diversity (ν), average heterozygosity (H
a
, 
H
c
), intrapopulational genetic differentiation (δ
T
), ge-
netic distance (d
0
) and value of the χ2 test of homogene-
ity of genetic structures by loci, with significance level α 
= 0.05 (*), α = 0.01 (**), α = 0.001 (***) for 17 polymor-
phic loci. Bold type indicates significant deviation (p < 
005) of genotype frequencies from Hardy-Weinberg 
equilibrium, underlined values indicate a significant 
heterozygote deficiency.
Preglednica 4: Primerjava kazalnikov genetske vari-
abilnosti pri podsajenih populacijah bukve Brička (BRI) 
in Kladje  (KLA): število alelov na lokus (A/L), alelna 
raznolikost (ν), povprečna heterozigotnost (H
a
, H
c
), 
genetska diferenciacija med osebki znotraj populacije 
(δ
T
), genetska razdalja (d
0
) in vrednost χ2 testa homog-
enosti genetskih struktur po lokusih, z nivojem 
značilnosti  α = 0,05 ( *), α = 0,01 (**), α = 0,001 (***) za 
17 polimorfnih lokusov. Krepki tisk označuje značilno 
odstopanje (p < 0,05) frekvenc genotipov od Hardy-
Weinbergovega ravnotežja, podčrtane vrednosti 
označujejo značilni deficit heterozigotov.
Locus 
(Lokus)
A/L ν δ
T
 (%) H
a
 (%) H
c
 (%) d
0
 (%)
χ
2
 value 
(χ
2
 vrednost)
BRI KLA BRI KLA BRI KLA BRI KLA BRI KLA
Aat-A 2 2 1.13 1.06 11.4 5.9 12.0 6.0 100 100 3.0 n.s.
Aat-B 2 2 1.79 1.70 44.7 41.6 36.0 22.0 51.5 37.9 4.0 n.s.
Aco-A 2 2 1.06 1.02 5.9 2.0 6.0 2.0 100 100 2.0 n.s.
Aco-B 3 2 1.46 1.20 31.8 16.5 28.0 18.0 73.7 100 10.0 n.s.
Idh-A 2 2 1.42 1.37 29.8 27.2 24.0 24.0 66.7 75.0 2.0 n.s.
Mdh-A 2 2 1.02 1.22 2.0 18.2 2.0 20.0 100 100 9.0 7.792**
Mdh-B 4 4 1.90 1.34 47.9 25.4 40.0 28.0 66.7 100 19.0 14.495**
Mdh-C 2 2 1.60 1.42 37.9 29.8 42.0 32.0 84.0 88.9 7.0 n.s.
Mnr-A 2 3 1.15 1.30 13.2 23.5 6.0 26.0 42.9 100 6.0 n.s.
Per-A 2 2 1.68 1.57 40.7 36.8 52.0 48.0 92.9 100 4.0 n.s.
Per-B 3 3 1.42 2.29 29.8 56.9 26.0 48.0 76.5 52.2 29.0 20.822***
Pgi-B 2 2 1.17 1.02 14.9 2.0 16.0 2.0 100 100 7.0 5.701*
Pgm-A 2 2 1.92 1.20 48.5 16.5 44.0 18.0 55.0 100 31.0 25.976***
Skdh-A 2 2 1.02 1.08 2.0 7.8 2.0 4.0 100 50.0 4.0 n.s.
6-Pgdh-A 2 3 1.24 1.11 19.8 9.7 14.0 6.0 63.6 60.0 7.0 n.s.
6-Pgdh-B 2 2 1.27 1.20 21.3 16.5 12.0 18.0 50.0 100 3.0 n.s.
6-Pgdh-C 4 4 1.49 1.75 33.1 43.2 38.0 36.0 100 64.3 17.0 n.s.
Gene pool 
(Genski sklad)
2.40 2.40 1.34 1.28 25.6 22.3 23.5 21.1 77.9 84.0 9.6
Genetic variation among individuals within an in-
dividual population, independent of the population 
size or the number of studied individuals, is defined by 
the level of genetic differentiation (δ
T
). The average lev-
els of genetic (allele) differentiation δ
T
 in the sampled 
populations of under-planted beech range from 22.3 % 
(Kladje) to 25.6 % (Brička), which corresponds to a 
ratio of 1:1.15. Observed frequencies of genotypes at the 
majority of loci correspond to the frequencies of geno-
types expected according to Hardy-Weinberg equilib-
rium. We found significant deviation from a Hardy-
Weinberg structure at the Brička site at the loci Mnr-A, 
Per-A and 6-Pgdh-B and at the Kladje site at loci Aat-B, 
Per-A and Skdh-A. In the Kladje sample population, a 
significant deficiency of heterozygotes also appeared at 
locus Aat-B. According to the Hardy-Weinberg law, de-
viation of expected genotype frequencies from the Har-
dy-Weinberg structure suggest that random mating 
does not exist, that there is gene flow into the popula-
tion or that natural selection is in operation. The high-
est realised level of heterozygosity (H
c
) in the sampled 
populations is from 77.9 % (Brička) to 84.0 % (Kladje). 

13
G. BOŽIČ, L. KUTNAR & M. ZUPANČIČ: GENETIC VARIABILITY AND SUITABILITY OF UNDER-PLANTED BEECH IN SELECTED ...
FOLIA BIOLOGICA ET GEOLOGICA 52/1-2 – 2011
The calculated value (H
c
) for both sample populations 
together, though, indicates a deficiency of heterozy-
gotes in comparison with the highest achievable values, 
which equals 100 %. However, because of the lack of 
data on the origin of the parental stands of beech and 
past development phases of the groups of trees under-
planted in the spruce monocultures on Pohorje includ-
ed in the analysis, we cannot establish whether the re-
productive system, the method of obtaining them and 
the use of forest reproduction material and/or various 
forms of (survival) selection influenced this phenome-
non. 
4.3 Genetic differentiation between the sampled 
populations
The frequency of individual alleles at some loci (e.g., 
Pgm-A
2
 (9 % vs. 40 %), Per-B
1
 (11 % vs. 37 %), Mdh-B
4
 
(5 % vs. 16 %), Mdh-A
1
 (1 % vs. 10 %), 6-Pgdh-C
4
 (8 % vs. 
23 %)) partially indicates great diversity of the stands. If 
we compare the allele distribution of the sample popula-
tions of under-planted beech, the probability of deviati-
ons from homogeneous allele structures is statistically 
significant at 5 of the 17 analysed loci (Table 4). The cal-
culated values show that deviations from the homogene-
ity of allele distributions are highly significant at loci 
Per-B and Pgm-A (α = 0.001), Mdh-A (α = 0.01) and, at a 
level of risk α = 0.05, also at Mdh-B and Pgi-B. The share 
of alleles that do not differentiate the test populations 
(d
0
), for the genetic fund of 17 polymorphic loci, amo-
unts on average to 9.6 %. In a comparison of individual 
loci, we also find high values of genetic distance. The 
sample groups of beech, which at locus Pgm-A are sepa-
rated into 31 % allele and 44 % genotype shares, and at 
loci Per-B and Mdh-B into 29 % or 19 %  allele and 38 % 
or 26 % type shares, respectively, already allow the fin-
ding of major genetic differentiation between them. The 
hypothesis that the sample groups of beech under-plan-
ted in the two spruce monocultures on Pohorje (Brička 
in Kladje) have a similar genetic structure, cannot there-
fore be confirmed.
In th e sel ected sp ruce m o n ocul tur es o n P o h o rje, th e 
population of under-planted beech at the Brička site has 
greater effective allele diversity, hypothetical multi-locus 
gametic diversity, observed heterozygosity and greater 
differentiation among individuals within the population 
in the gene pool than the population of under-planted 
beech at the Kladje site. The reasons for the different 
comparative values of the individual sample populations 
are not known. The established differences in the level of 
genetic variability may reflect different sources of prov-
enance, historical differences in interventions in the 
area of the parental stands, differences in the method of 
obtaining and using the forest reproductive material 
and/or different forms of survival selection of juvenile 
beech, both in the parental and in the new, changed con-
ditions of their living environment. These are only theo-
retical suppositions, of course, which have not in this 
case been verified. Additional research of the genetic 
structure of beech stands with natural regeneration that 
have survived the period of spruce monocultures in the 
area of Pohorje is recommended, in order to know 
whether the analysed genetic structure of the sampled 
beech in our research was representative or not. 
The first evidence of the existence of genetic differ-
ences between the studied groups of under-planted 
beech at the Brička and Kladje sites is provided by the 
result of a statistical test of homogeneity of allele struc-
ture at polymorphic gene loci. Among the allele distri-
butions of sampled populations of beech, we obtained 
significant deviations at 5 of 17 loci. The level of ana-
lysed genetic differentiation between the sampled popu-
lations is relatively large. Between the groups of under-
planted beech in selected spruce monocultures in the 
southern part of Pohorje, the genetic differentiation (d
0
) 
is expressed by the share of alleles that do not distin-
guish the two populations, 9.6 %. This finding is similar 
to the established values of allele (genetic) distance (d
0
; 
Gregorius 1974) among the most differentiated popu-
lations of beech in Bavaria (Germany), which differed in 
a range from 2.6 % to 10.9 % (Konnert & Henkel 1997). 
Similarly high values of genetic differentiation, estab-
lished among the four populations with the most differ-
ent habitats, is also cited by research of twenty autoch-
thonous populations of beech from the area of western 
Germany (Turok 1994). 
The observed deviation between the sampled popu-
lations from Brička and Kladje on Pohorje, in the event 
of representativeness of the genetic structures of the 
studied populations, may indicate that the gene flow be-
tween the parental stands of beech was limited or that 
the greater genetic differentiation may also be a conse-
quence of isolation and specific selection processes that 
the beech at these locations experienced. This could also 
mean that the planting material that was under-planted 
5. DISCUSSION

14
G. BOŽIČ, L. KUTNAR & M. ZUPANČIČ: GENETIC VARIABILITY AND SUITABILITY OF UNDER-PLANTED BEECH IN SELECTED ...
FOLIA BIOLOGICA ET GEOLOGICA 52/1-2 – 2011
in Brička and Kladje does not derive from the same pa-
rental origin of beech. All these links can certainly not 
be understood in greater detail and their impact evalu-
ated without new, in-depth research. The results of our 
investigation thus point to the conclusion that the group 
of beech trees in the spruce monoculture at Brička is ge-
netically slightly different from the group of beech trees 
in the spruce monoculture of Kladje. 
With under-planting of beech in spruce monocul-
tures (without including naturally regeneration of beech), 
there is a constant danger of the loss of alleles (or genetic 
information) because of genetic drift, which can occur in 
small, isolated populations because of a reduction of the 
original size of the population during development and 
growth of the future beech stand. This danger is poten-
tially greater in our case for the Kladje beech population, 
which shows a lower level of intra-population genetic 
variability and has a larger share of rare alleles (with fre-
quencies <  5 %) than the Brička beech population. 
Silviculture treatment is a crucial step in the devel-
opment of forest. The use of natural regeneration in 
stands is therefore recommended for the renewal of for-
ests. In cases in which this is not possible, forest repro-
ductive material (seeds and pullings) obtained from 
neighbouring seed stands should be used. Collection and 
use of forest reproductive material is regulated by the Act 
on Forest Reproduc t ive Mater ia l (U LR S, no. 58/02 , 85/02 , 
45/04) and the Regulation for approval of basic material 
for production of forest reproductive material (FRM) of 
the categories “source indentified” and “selected” and 
the national list of basic material (URLS, no. 91/03). »For 
the majority tree species (primarily beech, pedunculate 
oak, sessile oak, fir and spruce), the use of seeds and 
seedlings within the altitudinal belt and provenance re-
gion from which it comes or from a neighbouring region 
is recommended. The use of seeds and seedlings from 
other regions of provenance is less recommended, and 
only exceptionally does either the forester or silviculture 
expert prescribe also the use of seeds and seedlings from 
neighbouring altitudinal zones. For minority tree spe-
cies, the whole of Slovenia is considered a uniform region 
of provenance, divided into 4 altitudinal belts. Neverthe-
less, even for these species, the use of seed in the region 
from which it originates is recommended« (Medved et 
al. 2011, p. 137). Forest seed is genetic material, so the 
selection of forest seed sources has far-reaching conse-
quences. There are not a large number of high-quality 
seed sources or stands and, because of the general change-
ability of forests and because of the anthropogenic bur-
dening of forests to date, there are ever fewer. In order to 
spread the risk and as a condition of the ecological adapt-
ability of forests, forest seed sources must embrace a suf-
ficiently large biological diversity, i.e., all the more im-
portant tree species with their local races and their ge-
netic variability. This is especially important given the 
present fast climate change and other anthropogenically 
caused uncertainties. Biological diversity and its adapta-
tion to local ecological conditions can still be expected in 
well-preserved natural and autochthonous forests. 
Only one seed stand is approved for obtaining forest 
reproductive material in the Pohorje region of prove-
nance, namely provenance Osankarica (ident. no. GSO: 
2.0 1 1 9 ) a t an al ti tude o f 1 240 m, » sel ected « ca teg o ry 
(Kraigher, Božič & Verlič 2011). This seed stand is 
also proposed as a forest genetic reserve in Slovenia and 
dynamic gene conservation unit on the European level 
(Westergren, Božič & Kraigher 2010). Pullings are 
also used for conversion spruce monocultures on Po-
horje, collected in a “selected” category seed stand (ident. 
number GSO: 4.0175, provenance Temenjak) in vicinity 
(Kraigher, Božič & Verlič 2011 ). An approved seed 
stand at an altitude from 650 to 700 m is classified in the 
Savinjska-Šaleška ecological sub-region (code 4.3) of the 
Prealpine provenance region (Kutnar et al. 2002).
There are relatively few preserved beech forests on 
Pohorje. The majority of these have been transformed 
into spruce monocultures. In addition, Pohorje is over-
grown with natural spruce forests, especially at higher 
altitudes, i.e., in the altimontane and lower sub-alpine 
zone. The montane zone is covered with fir forests. The 
natural possibilities of the preserved genetic heritage of 
beech are limited in area and the structure of stands in 
these areas is relatively poor. Seed beech trees are rare, 
the majority are stump-grown or mixed stands of 
stump-grown and seed trees. Regardless of the stand 
form, it will be necessary to a certain extent additionally 
to select for seed stands, even though the area may be 
very limited. Additional seed stands could be chosen in 
the Pohorje provenance region or in similar ecological 
conditions in neighbouring provenance regions (alpine 
and subalpine). In all cases, these are stands that are 
placed in the associations (syntaxa) Luzulo-Fagetum 
Meusel 1937, Hieracio rotundati-Fagetum Ž. Košir 1994 
and Cardamine savensi-Fagetum Ž . K o š i r 1 9 6 2 v a r . 
geogr. Abies alba Ž. Košir 1994 in the montane/altimon-
tane zone and the associations (syntaxa) Castaneo-Fage-
tum sylvaticae Marinček & Zupančič ( 1979 ) 1995 and 
Hedero-Fagetum Ž. Košir (1962) 1994 var. geogr. Polys-
tichum setiferum Ž. Košir 1994 in the colinar zone. 
We propose an enlargement of the network of seed 
stands on Pohorje (including Rdeči breg) and Kobansko, 
with the aim of exploiting existing potentials of beech 
that has survived the period of spruce monocultures for 
the needs of renewal of these complexes with the use of 
habitats of adapted planting material. The importance 
of this measure is in preparation of a high-quality base 

15
G. BOŽIČ, L. KUTNAR & M. ZUPANČIČ: GENETIC VARIABILITY AND SUITABILITY OF UNDER-PLANTED BEECH IN SELECTED ...
FOLIA BIOLOGICA ET GEOLOGICA 52/1-2 – 2011
of planting material suitable for under-planting beech in 
s p ru c e m o n o c ul t ur e s o n P o h o rj e , wi th s im ul t an e o u s 
preservation of the adaptation potential for growth and 
development of beech in suitable areas of degraded for-
ests in the light of possible climate change. Economi-
cally interesting conifers, such as spruce and fir, have a 
relatively large share in the timber stock of very varied 
forest associations in Slovenia. However, the surface 
share of potential forest communities in which conifers 
predominate is relatively small. Model-based forecasts 
indicate that this share will probably be further reduced. 
As has been established for Western and Central Europe 
(Kienast, Brzeziecki & Wildi 1998; Lexer et al. 2002, 
Maracchi, Sirotenko & Bindi 2005; Koca, Smith & 
Sykes 2006), it can also be expected in Slovenia that 
there will be a pronounced replacement of coniferous 
with deciduous forests (Kutnar, Kobler & Bergant 
2009; Kutnar & Kobler 2011). Simulations of climatic 
effects on spruce indicate an explicit fall in the share and 
worsened prospects of this species with the realisation 
of generally applicable climate scenarios, which envis-
age further atmospheric warming in the future (Ogris 
& Jurc 2010, Kobler & Kutnar 2010). 
The problem of seed sources of beech on Pohorje 
therefore deserves particular attention. The work of pre-
serving seed sources and the biological diversity of for-
ests should include both the protection of seed sources 
with the aid of legislation and regulations and the pro-
tection of seed sources by means of the status of special 
purpose forests and other forestry nature conservation 
efforts for preserving the natural genetic heritage by 
protecting and supplementing the network of forest gene 
reservoirs and other areas with important seed sources. 
It is also sensible to continue directly applicable research 
and development work for the needs of the forest seed 
and sapling trade, including in depth research into the 
genetic characteristics of populations of forest tree spe-
cies in Slovenia. 
6. CONCLUSIONS
On the basis of the results of analysis of the genetic 
structure of under-planted juvenile beech in selected 
s p ru c e m o n o c ul tur e s o n P o h o rj e wi th i s o zym e g e n e 
markers, we conclude: 
• Under-planted beech at the Brička site are geneti-
cally slightly different from the under-planted beech 
at the Kladje site. 
• The genetic variability of under-planted beech 
within individual populations, according to indica-
tors of genetic diversity (H
a
, ν, ν
gam
, δ
T
) is greater at 
the Brička site that at the Kladje site.
• There is greater potential danger of the loss of ge-
netic information (alleles) because of genetic drift at 
the Kladje site, which can occur in smaller, isolated 
populations in the development of future stands 
(than in the population at the Brička site).
• The allele (genetic) distance among under-planted 
beech at the Brička and Kladje sites, which we calcu-
lated according to Gregorius (1974), is relative 
large for the studied gene pool (d
0
 = 9.6 %).
• The problem of seed sources of beech on Pohorje 
deserves special attention. There is a need to select 
relatively well-preserved beech stands on the most 
varied potential forest sites on Pohorje and Koban-
sko, which could be selected as seed stands.  
POVZETEK
Uvod
V začetku devetdesetih let so vetrolomi in gradacije 
podlubnikov zmanjšali stabilnosti smrekovih nasadov v 
Evropi  in povzročili opazno zmanjševanje vitalnosti, ki 
smo mu bili priča do konca prejšnjega desetletja. Goz-
darska stroka si je prizadevala najti načine za povečanje 
dolgoročne stabilnosti in ohranitev trajnosti teh nasa-
dov, kar je vodilo v izbor rastišču primernejših drevesnih 
vrst. Zaradi vprašljivega golosečnega načina gospodarje-
nja in pritiska s strani javnosti ter zahtev po povečanju 
trajnosti je postal v Evropi vnos s podsadnjo listavcev v 
iglastih gozdovih široko uveljavljen gozdnogojitven 
ukrep. Gozdnogojitvena izhodišča so bila za tovrstne 
premene razmeroma slabo opredeljena. 
V zadnji polovici prejšnjega stoletja je bila premena 
čistih smrekovih sestojev ( Picea abies L. Karst.) eden po-
glavitnih gojitvenih izzivov v Evropi (Zerbe 2002;  Teu-
ffel, Heinrich & M. Baumgarten 2004). Ocenjujejo, 
da je v Evropi najmanj 6 do 7 milijonov hektarov čistih 
smrekovih sestojev zunaj svojih naravnih rastišč, od ka-
terih je 4-5 milijonov hektarov osnovanih na rastiščih, 

16
G. BOŽIČ, L. KUTNAR & M. ZUPANČIČ: GENETIC VARIABILITY AND SUITABILITY OF UNDER-PLANTED BEECH IN SELECTED ...
FOLIA BIOLOGICA ET GEOLOGICA 52/1-2 – 2011
kjer bi sicer prevladovali listnati ali mešani iglasto-li-
stnati gozdovi. Sedanje stanje je posledica gozdnogo-
spodarskih odločitev v preteklosti, ko so bili mešani se-
stoji izpostavljeni kmetijskemu izkoriščanju, steljarje-
nju, paši in pridobivanju lesa za kurjavo (Johann s sod. 
2004). Velika potrebe po lesu zaradi industrializacije je 
vodila v pospeševanje monokultur hitrorastočega drev-
ja. V zadnjih 200 letih je bila smreka najpogosteje izbra-
na kot drevesna vrsta za umetno obnovo sestojev zaradi 
hitre rasti, preprostega osnovanja sestojev, majhnih zah-
tev glede redčenj in zaradi ne pretirano obremenjajoče-
ga objedanja divjadi.
Vnos smreke zunaj njenega naravnega areala je po-
vezan s številnimi, v glavnem kratkoročnimi koristmi. 
Vrsta je ekonomsko zelo zanimiva, ima potencial za 
proizvodnjo visokokakovostnega lesa v kratkih časov-
nih obdobjih. Evropski listnati gozdovi so v preteklosti 
pokrivali občutno večje površine, kot jih pokrivajo 
danes, zato velja v Evropi splošno mnenje, da je snova-
nje listnatih sestojev korak k trajnostnemu gozdarstvu 
(Hannah, Carr & Lankerani 1995; Stanturf & 
Madsen 2002). Eden od načinov osnovanja je premena 
smrekovij v listnate ali v mešane gozdove. Premena v 
Evropi široko razširjenih homogenih smrekovij v na-
ravne listnate gozdove se uporablja v gozdarski praksi 
zadnjih 50 let.
V prid premeni govori več dejavnikov. Smreka se je 
v velikih primerih pokazala kot nestabilna, izpostavlje-
na je zmanjšanju vitalnosti, vetrolomom, napadom pod-
lubnikov, suši in negativno vpliva na tla (Larsen 1995). 
Občutne spremembe v okolju in krajini s posledicami na 
spremembe ali zmanjševanje biotske raznolikosti (Gra-
bherr & Koch 1993) so zmanjšale naklonjenost javnega 
mnenja. Klimatske spremembe in posebno naraščajoča 
verjetnost pojavljanja klimatskih ekstremov kot npr. ne-
urij so izpostavile ranljivost smrekovih monokultur in 
poudarjajo potrebo po zmanjševanju tveganja z vključe-
vanjem ostalih drevesnih vrst v smrekove sestoje (Brad-
shaw s sod.  2001 ). Dvig cen lesa listavcev je zmanjšal 
ekonomsko upravičenost snovanja antropogenih igla-
stih sestojev (Abildtrup, Riis & Jellesmark-Thorsen 
1997; Spiecker 2000).
Za uspešno premeno je podsadnja z bukvijo (Fagus 
sylvatica L.) bodisi pod zastorom matičnega sestoja ali v 
svetlobnih jaških možna alternativa golosečnemu nači-
nu gospodarjenja, ki je v Evropi še vedno prisotno. Pod-
sadnja je star gojitveni postopek, ki je danes deležen 
nove pozornosti (Otto 1986; Spellmann & Wagner 
1993). Prednosti podsadnje so manjše zapleveljevanje, 
ugodnejša mikroklima, varstvo pred poznimi pozebami 
(Löf 2000), kot tudi večja stopnja naklonjenosti javnega 
mnenja v nasprotju z golosečnjami (Mattsson & Li 
1994). 
V Sloveniji so s premenami začeli spreminjati čiste 
smrekove sestoje v mešane sredi 20. stoletja. Čeprav so 
gozdovi v Sloveniji v primerjavi s Srednjo Evropo raz-
meroma ohranjeni, pa zaradi dediščine preteklosti tre-
nutna drevesna sestava gozdov odstopa od ocenjene na-
ravne (Diaci &  Grecs 2003). Delež smreke v lesni zalo-
gi je 32 %, ocena naravnega deleža je približno 8 %. Slo-
v e n i j a j e d e ž e l a l i s t n a t i h , p r e d v s e m b u k o vi h g o z d o v 
(Šercelj 1996, Ž. Košir s sod. 1974, Dakskobler 2008). 
70 % gozdov Slovenije uvrščamo v združbe, v katerih je 
bukev vodilna vrsta.
Obdobje aktivne premene nasadov smreke ima za-
četke v zgodnjih 50. letih z navodili Ministrstva za goz-
darstvo za pričetek kampanje sadnje plemenitih listav-
cev v nasade smreke, predvsem gorskega javorja (Diaci 
2006). Prizadevanja večinoma niso bila uspešna zaradi 
previsokih gostot velikih rastlinojedov (Diaci 2006 
povzeto po ustnem viru Mlinšek 2004). Bistveno boljši 
je bil uspeh uresničevanja prvih ureditvenih načrtov po 
drugi svetovni vojni. Mlinšek je leta 1954 izdelal obse-
žen ureditveni načrt za enoto Mislinja, ki je zajemal 
predvsem nasade smreke (Mlinšek 1955). Pričel je s po-
stopno premeno na osnovi kontrolne metode s podrob-
nimi analizami prirastka, uvedel izbiralna redčenja in 
podaljšal obhodnje, vpeljal celovito metodologijo pod-
sadnje nasadov smreke s sadikami in puljenkami bukve 
ter posamično in skupinsko zaščito proti objedanju, za-
govarjal je rastiščem prilagojen pristop. Preizkušali so 
različne metode posamične zaščite in dosegli precejšnje 
uspehe s cementno malto. Zaradi pomanjkanja semen-
skih dreves bukve in sadik, so puljenke bukve prenašali 
iz bolj ali manj primerljivih rastišč na severni strani Po-
horja (Diaci 2006).
Da bi ocenili genetsko variabilnost podsajene bukve 
v čistih smrekovih sestojih na Pohorju, smo v juvenilni 
fazi razvoja bukve opravili genotipsko analizo testnih 
populacij z uporabo biokemijskih genskih označeval-
cev. Namen študije je z metodo analize izoencimov oce-
niti stopnjo genetske sorodnosti populacij podsajene 
bukve. Preizkusiti želimo hipotezo, da imajo testne po-
pulacije bukve podobno populacijsko genetsko struktu-
ro in ne nakazujejo večjih odstopanj v povprečnih vre-
dnostih parametrov. Z raziskavo želimo prispevati k 
podrobnejšemu poznavanju genetskih struktur, genet-
ske raznolikosti in genetske diferenciranosti bukovih 
populacij, ki so jih vnesli v smrekove monokulture na 
Pohorju.   
Študijsko območje 
Pohorje je izrazita gorska planota, leži v višini 1200-1500 
m ter je podaljšek Centralnih Alp. Masiv je zgrajen iz 

17
G. BOŽIČ, L. KUTNAR & M. ZUPANČIČ: GENETIC VARIABILITY AND SUITABILITY OF UNDER-PLANTED BEECH IN SELECTED ...
FOLIA BIOLOGICA ET GEOLOGICA 52/1-2 – 2011
metamorfnih in magmatskih kamenin ter sedimentov 
(Budnar-Tregubov 1958). Klima je sredogorska. V za-
dnjih 4000 do 5000 letih so v prvotnih gozdovih prevla-
dovale različne oblike jelovo bukovih gozdov ob skro-
mni udeležbi smreke (Culiberg & Šercelj 2000). Prvo-
bitne gozdove na Pohorju so sestavljale predvsem bukev, 
jelka in smreka, ponekod pa je bil primešan tudi mace-
sen (Breznikar s sod. 2006). Naravni smrekovi gozdovi 
so edafsko pogojeni in s tem omejeni na zamočvirjene 
zaravnice, skledaste uleknine in na blago nagnjena po-
bočja na pohorskem platoju. V zadnjih dveh stoletjih je 
bila drevesna sestava pohorskih gozdov spremenjena. 
Danes tu prevladujejo antropogeno spremenjeni smre-
kovi sestoji. Zaradi negativnih vplivov spremenjene dre-
vesne sestave je ogrožena tudi trajnost donosov iz gozda 
(Breznikar s sod. 2006). V preteklosti se je v obdobju 
od leta 1800 do konca druge svetovne vojne zaradi vpli-
va nemške šole gospodarjenja z gozdovi in njenih polje-
delskih načel v pohorske gozdove intenzivno vnašala 
smreka, obnova gozda pa je bila usmerjena v osnovanje 
čistih smrekovih sestojev. Po drugi svetovni vojni so se 
ta gozdnogojitvena načela postopoma opuščala. Antro-
pogeni smrekovi sestoji na Pohorju, med katere sodijo 
sestojne zgradbe s prevladujočim deležem smreke na 
bukovih in jelovih rastiščih, pokrivajo danes 27 000 ha 
oziroma 45 % skupne gozdne površine na Pohorju (Bre-
znikar s sod. 2006).
Negativne posledice spremenjene drevesne sestave 
narekujejo iskanje ustreznih ukrepov pri gospodarjenju 
z gozdovi, s katerimi bi postopoma vzpostavili bolj na-
ravno zmes drevesnih vrst v gozdnih sestojih. Načrtova-
nje ukrepov v smrekovih monokulturah zahteva pozna-
vanje procesov degradacije rastišča zaradi negativnega 
vpliva pospeševanja smreke na bukovih in jelovih rasti-
ščih. Pri prevladujočem deležu smreke v sestoju se začne 
na tleh kopičiti surov humus, k njegovemu škodljivemu 
delovanju pa dodatno prispeva labilnost tal. Smreka za-
radi plitvega koreninjenja premočno izkorišča zgornje 
talne horizonte, spodnji talni horizonti pa se začno zgo-
ščevati. Pride do poslabšanja fizikalnih lastnosti tal 
(zmanjševanje zračnosti), povečuje se kislost tal, zmanj-
šuje se dostopnost hranilnih snovi, zmanjša se intenziv-
nost humifikacije in mineralizacije organskih snovi v 
tleh, prične se kopičenje neugodnih  oblik humusa. S po-
stopnim zbijanjem talnega profila in dviganjem nepro-
pustnega horizonta se zmanjšuje biološko aktivna globi-
na tal, zaradi slabših fizikalnih lastnosti tal pa se zmanj-
ša kapaciteta tal za vodo. Vlažne oblike surovega humu-
sa in mahovi povečujejo površinsko akumulacijo pada-
vinske vode in pogojujejo procese pseudooglejevanja tal 
(Breznikar s sod. 2006). 
Razvoj stabilnejših gozdnih struktur in zaviranje 
degradacijskih procesov v gozdnih tleh so glavni strate-
ški cilji pri načrtovanju razvoja gozdov na Pohorju. Na-
črtni posegi za sanacijo spremenjenih sestojnih zgradb 
in usmerjeno gozdnogojitveno ukrepanje so se začeli na 
mislinjskem delu Pohorja v petdesetih letih prejšnjega 
stoletja in se postopoma širili na celotno območje Po-
horja. Glavni ukrep sanacije je vnos listavcev, predvsem 
bukve, v smrekove sestoje in izločitev vpliva preštevilne 
divjadi na gozdno mladje.
Raziskovane objekte na Pohorju smo izbrali na južni 
strani Pohorja na raziskovanih ploskvah Gozdarskega 
inštituta Slovenije in sicer na lokaciji Brička nad Mislinj-
skim jarkom ( ZGS O E Sloven j Gradec ) in Kladje pri 
O s a n k a r i c i ( Z G S O E M a r i b o r ) ( P r e g l e d n i c a 1 ) . O b a 
objekta je pred intenzivnejšimi posegi in degradacijski-
mi procesi domnevno poraščal bukov ali jelovo-bukov 
gozd s primesjo smreke. Navedeni lokaciji veljata za po-
tencialno naravno rastišča acidofilnega bukovja z belka-
sto bekico, geografska varianta s trilistno penušo (Lu-
zulo albidae-Fagetum Meusel 1937 var. geogr. Cardami-
ne trifolia (Marinček 1983) Marinček & Zupančič 1995). 
Na robu objekta Brička še danes na manjši površini raste 
razmeroma dobro ohranjen acidofilni bukov gozd. Širše 
območje objekta Kladje je precej spremenjeno, vendar 
na osnovi posameznih ostankov tovrstnega gozda lahko 
sklepamo na potencialna rastišča asociacije. Vendar pa 
je na širšem območju tega dela Pohorja bila kartirana 
združba bukve z zasavsko konopnico. To je conalna 
združba pohorskega visokogorskega bukovega gozda, ki 
naseljuje zgornji del montanskega pasu masiva Pohorje, 
to je v nadmorskih višinah od 1000 do 1300 m. Poleg 
značilnih drevesnih vrst bukve in gorskega javorja se v 
razmeroma dobro ohranjenih sestojih te združbe poja-
vljata z večjim deležem tudi jelka in smreka. Na osnovi 
tega je bila opredeljena posebna geografska varianta te 
združbe z jelko (Cardamini savensi-Fagetum Ž. Košir 
1962 var. geogr. Abies alba Ž. Košir 1979). 
Zaradi pospeševanja smreke v preteklosti območje 
objektov porašča smrekova monokultura. Izhodišča za 
izbiro raziskovalnih objektov so poleg zahteve po za-
smrečenih potencialnih bukovih rastiščih zajemala še 
prisotnost večjega števila vitalnih podsajenih dreves 
bukve znotraj posamezne ploskve, podobno starost vne-
sene bukve na primerjalnih lokacijah ter možnosti za 
vpetost raziskovalnih objektov v okvire drugih preuče-
vanj. Raziskovalna objekta gradijo zrela drevesa smreke 
in podsajene bukve v juvenilni fazi razvoja. Značilnosti 
izbranih raziskovalnih ploskev so navedene v pregledni-
ci št. 1. Na ploskvi Brička nad Mislinjskim jarkom je plo-
skev poraščalo 173 smrek / ha z ocenjeno lesno zalogo 
smrekovega sestoja na 477 m
3 
/ ha, na ploskvi Kladje pri 
Osankarici pa 126 dreves / ha z lesno zalogo 302 m
3 
/ ha 
(Čater 2011). V letu 2006 je bila starost vzorčene podsa-
jene bukve ocenjena na okoli 10 do 15 let (Čater 2011).

18
G. BOŽIČ, L. KUTNAR & M. ZUPANČIČ: GENETIC VARIABILITY AND SUITABILITY OF UNDER-PLANTED BEECH IN SELECTED ...
FOLIA BIOLOGICA ET GEOLOGICA 52/1-2 – 2011
Material in metode
Nabiranje vzorcev
Na raziskovalnih objektih Brička in Kladje na Pohorju 
smo za genetske analize vzeli vzorec stotih naključno 
izbranih dreves bukve. V vzorec na vsaki ploskvi v veli-
kosti 100 m x 100 m smo enakomerno zajeli vitalna dre-
vesa posajene bukve. Z vsakega od poskusnih dreves 
smo v zimskem obdobju leta 2005 / 2006 odvzeli vejo s 
spečimi popki, ki smo jih uporabili za ekstrakcijo enci-
mov. Popke smo do analize hranili v epruvetah pri tem-
peraturi -20° C. Velikost vzorca je bila 50 dreves na po-
samezno ploskev.
Analiza izoencimov
Raziskave genetskih značilnosti bukve smo izvedli z 
metodo analize izoencimov na škrobnem gelu. Razisko-
vani material so speči popki. Encimske izvlečke smo ek-
strahirali iz bukovih popkov po že preizkušenih meto-
dah. Genotip vsakega drevesa smo ugotavljali s pomočjo 
horizontalne elektroforeze na škrobnem gelu. Ekstrak-
cijo encimov iz spečih popkov, elektroforezo, barvanje 
gelov in odčitavanja elektroforegramov smo izvajali po 
standardiziranih metodoloških postopkih za analizo 
bukovih vzorcev (Konnert, Hussendoerfer & Dou-
navi 2004). Laboratorijski del analiz smo izvedli febru-
arja 2006 v okviru nalog raziskovalnega projekta Di-
namika ogljika v naravnem bukovem gozdu (L4-6232). 
Analize smo izvedli v genetskem laboratoriju Bayerische 
Amt für forstliche Saat- und Pflanzenzucht v Teisendor-
fu, Nemčija, pod vodstvom dr. Monike Konnert. 
V analize smo zajeli 10 encimskih sistemov, ki jih 
kodira 17 genskih lokusov (preglednica št. 2). Rezultate 
izoencimskih analiz smo vrednotili z relativnimi fre-
kvencami alelov in genotipov po posameznih genskih 
lokusih Genetsko strukturo populacije smo opisali na 
osnovi pogostosti pojavljanja posameznih alelov na po-
limorfnih lokusih. Kot polimorfen lokus smo upoštevali 
vsak genski lokus, na katerem smo ugotovili vsaj še en 
alel, ne glede na njegovo relativno pogostost v populaciji 
(brez kriterija).
Frekvenčne porazdelitve alelov na lokusih smo po 
posamezih populacijah opisali s 4 alelnimi profili, ki 
smo jih določili po Finkeldeyu (1993), in sicer kot: i) 
fiksacijo, če je na posameznem genskem lokusu samo 1 
alel (alelna frekvenca = 100 %), ii) nizko stopnjo poli-
morfizma, če je na posameznem genskem lokusu je pri-
soten pogosti alel (alelna frekvenca > 80 %) in eden ali 
več redkih alelov, iii) visoko stopnjo polimorfizma, če 
sta na posameznem genskem lokusu najmanj dva alela 
kot prevladujoča (alelna frekvenca > 20 %), iiii) netipični 
profil, če alelne strukture na posameznem genskem lo-
kusu ne moremo uvrstiti v 1., 2. ali 3. profil.  
Genetsko variabilnost znotraj posameznih popula-
cij smo interpretirali s parametri genetske pestrosti in 
genetske raznolikosti.  Pri parametru genetske pestro-
sti, ki v posamezni populaciji upošteva samo številčnost 
različnih genetskih tipov, smo izračunali tri parametre: 
(1) delež polimorfnosti analiziranih genskih lokusov (P 
%); (2) največje možno število različnih alelov (M
max
); 
(3) povprečno število alelov na polimorfni lokus (A/L). 
Pri parametru genetske raznolikosti, ki za razliko od 
parametra genetske pestrosti poleg števila različnih ge-
netskih tipov upošteva tudi njihovo pogostnost poja-
vljanja v populaciji, smo izračunali opaženo heterozigo-
tnost (H
a
) in pogojeno hetrozigotnost (H
c
; Gregorius, 
Krauhausen & Mueller-Starck 1986), efektivno 
alelno raznolikost (ν; Gregorius 1978, Gregorius 
1987), večlokusno hipotetično gametska raznolikost 
(ν
gam
) ter stopnjo genetske diferenciacije med osebki 
znotraj populacije (δ
T
; Gregorius 1987), ki je pri večjih 
vzorcih enaka stopnji pričakovanih hetrozigotnih dele-
žev, ki nastanejo pri panmiksični oplodnji (H
e
;  Nei 
1 973 ). Za preverjanje, kako se dejanski heterozigotni 
deleži v podsajenem mladju bukve razlikujejo od priča-
kovanih hetrozigotnih deležev, ki nastanejo pri panmi-
ksični oplodnji (Hardy-Wienbergovo ravnotežje) smo 
uporabili χ2 test, ki ga izvajamo po lokusih ločeno za 
vsako vzorčeno populacijo posebej, pri stopnji tveganja 
α = 0,05. 
Genetsko diferenciranost med vzorčenima popu-
lacijama podsajene bukve na lokacijah Brička ter Klad-
je smo podali z merilom povprečne genetske razdalje 
(d
0
; Gregorius 1974). Statistično primerjavo genet-
skih struktur bukve smo izvedli na osnovi χ2 testa ho-
mogenosti alelnih frekvenc po lokusih. Ničelno hipo-
tezo homogenosti alelnih porazdelitev med populaci-
jami zavračamo na nivoju tveganja α = 0,05. Za izračun 
posameznih parametrov genetske variabilnosti in sta-
tističnih primerjav smo uporabili program za ovre-
dnotenje podatkov izoencimskih analiz GSED (Gillet 
1998). 
Rezultati
V tej raziskavi želimo osvetliti predvsem genetski vidik 
premene monokultur smreke na Pohorju s podsadnjo 
b ukv e. C il j raziska v e j e ug o t o vi ti g e n etsk o struktur o 
podsajene bukve na lokacijah Brička in Kladje, to je na 
degradiranih potencialno naravnih rastiščih acidofilne-
ga bukovja z belkasto bekico, geografska varianta s trili-
stno penušo (Luzulo albidae-Fagetum Meusel 1937 var. 

19
G. BOŽIČ, L. KUTNAR & M. ZUPANČIČ: GENETIC VARIABILITY AND SUITABILITY OF UNDER-PLANTED BEECH IN SELECTED ...
FOLIA BIOLOGICA ET GEOLOGICA 52/1-2 – 2011
geogr. Cardamine trifolia Marinček (1983) Marinček & 
Zupančič 1995). Ugotoviti želimo ali so razlike v genet-
skih strukturah med skupinami dreves podsajene bukve. 
Rezultate genetskih primerjav prikazujemo v pregledni-
cah št. 3 in 4 za 17 polimorfnih genskih lokusov.
Frekvence alelov in genotipov
Iz relativnih alelnih frekvenc analiziranih lokusov je 
razvidno (preglednica št. 3), da je v populacijah poli-
morfnih vseh 17 analiziranih genskih lokusov (P = 100 
%). V obeh populacijah smo odkrili nizko stopnjo poli-
morfnosti na 3 lokusih (Aat-A, Aco-A, Skdh-A), visoko 
stopnjo polimorfnosti na 2 lokusih (Aat-B, Per-A). Po-
dobno polimorfnost nakazuje tudi lokus Idh-A. Netipi-
čen profil smo v obeh populacijah odkrili na 6 lokusih 
(Aco-B, Mdh-A, Mnr-A, Pgi-B, 6-Pgdh-A, -B). Razločen 
prehod med nizko in visoko stopnjo polimorfizma pri 
testnih populacijah smo ugotovili pri 5 lokusih. Lokusa 
Per-B in 6-Pgdh-C odražata nizek polimorfizem v vzor-
cu Brička in visok polimorfizem v vzorcu Kladje, med-
tem ko imajo lokusi Mdh-B, -C in Pgm-A nizek polimor-
fizem v vzorcu Kladje ter visok v vzorcu Brička. V obeh 
vzorčenih populacijah je vedno prisoten isti prevladajo-
či alel. Frekvenco glavnega alela smo odkrili v razponu 
od 54 % do 99 %. Frekvence nad 10 % lahko dosegajo še 
aleli Aat-B
2
, Aco-B
2
, Idh-A
2
, Mdh-A
1
, Mdh-B
4
, Mdh-C
1
, 
Per-A
1
, Per-B
1
, Pgm-A
2
, 6-Pgdh-A
4
, 6-Pgdh-B
1
, 6-Pgdh-
C
4
, medtem ko se drugi aleli pojavljajo v nizkih frekven-
cah. 
Alelne frekvence se na primer močno spremenijo 
pri alelih Mdh-B
4
, Per-B
1
, Pgm-A
2
 in 6-Pgdh-C
4
. Fre-
kvenci alelov Per-B
1
 in 6-Pgdh-C
4
 sta v vzorcu Brička 
nižji kot v vzorcu Kladje (11 % vs. 37 % in 8 % vs. 23 %), 
medtem ko sta alelni frekvenci Mdh-B
4
 in Pgm-A
2
 večji 
kot v vzorcu Kladje (16 % vs. 5 % in 40 % vs. 9 %). Zani-
miv e so tudi al eln e varian te Aat-A
1
, Mdh-B
2
, Pgi-B
3
, 
6-Pgdh-A
4
, 6-Pgdh-C
5
, ki so v populaciji Kladje le redko 
prisotne (to je s frekvenco manj kot 5 %) ter pogostnejše 
v populaciji Brička (do 11 %) oziroma alel Mdh-A
1
, ki je 
redek v populacij Brička (1 %) ter pogostnejši v popula-
ciji Kladje (10 %). 
Primerjava genotipskih frekvenc nakazuje na obstoj 
razlik med primerjanima vzorčenima populacijam na 
posameznih genskih lokusih in sicer na 7 od skupaj 17 
analiziranih genskih lokusov. Homozigotni in heterozi-
gotni tipi močneje ferkventni v vzorcu Brička v primer-
javi z vzorcem Kladje so: Per-B
22
 (70 % vs. 32 %), Pgm-
A
23
 (44 % vs. 18 %), Pgm-A
22
 (18 % vs. 0 %), Mdh-A
33
 
(98 % vs. 80 %), Mnr-A
33
 (90 % vs. 74 %), 6-Pgdh-C
15
 
(20 % vs. 4 %), Pgi-B
23
 (16 % vs. 2 %). Heterozigotni ali 
homozigotni tipi močneje ferkventni v vzorcu Kladje v 
primerjavi z vzorcem Brička so: Pgm-A
33
 (82 % vs. 38 %), 
Mdh-A
13
 (20 % vs. 2 %), Per-B
12
 (30 % vs. 14 %), Per-B
11
 
(20 % vs. 4 %), Mnr-A
35
 (20 % vs. 6 %) in Mdh-B
33
 (72 % 
vs. 54 %). 
Genetska variabilnost znotraj posameznih vzorčenih 
populacij 
Genetska pestrost
Izraz genetska pestrost se pomensko nanaša izključno 
na število genetskih kategorij (alelov, genotipov)  popu-
lacije ali njenih delov. Na celotnem območju preučeva-
nja smo v vzorčenih populacijah podsajene bukve na 17 
polimorfnih lokusih odkrili skupaj 43 različnih alelov 
(M
max
). V nobeni populaciji nismo odkrili vseh možnih 
alelnih variant. Celotna alelna pestrost je v pomladitve-
nih skupinah bukve zastopana od 93,0 % (Brička) do 
95,3 % (Kladje). Obe populaciji imata v povprečju enako 
število prisotnih alelov na lokus  (A/L = 2,40).  
Genetska raznolikost
Genetska raznolikost je variabilnost osebkov v popula-
ciji, ki jo izražajo frekvence različnih genetskih katego-
rij znotraj populacije. Merilo genske (alelne) raznoliko-
sti v populaciji je dejansko razpoložljivo ali efektivno 
število alelov na posameznem lokusu. Ker je prispevek 
redkih alelov (to je alelov s frekvenco < 5 %) k skupni 
v s o t i m a j h e n , t a m e r a i z r až a t u d i d e j an s k o s t o p n j o 
uravnoteženosti pogostih alelov. Primerjava srednjih 
vrednosti efektivnega števila alelov na lokus (ν) naka-
zuje na različnost vzorčenih populacij. Vrednosti se gi-
bljejo v razponu od 1,28 (Kladje) do 1,34 (Brička) kar 
ustreza razmerju 1:1,05. Ustrezno manjša vrednost 
efektivnega števila alelov na lokus pri vzorčeni popula-
ciji Kladje z vrednostjo A/L = 2,40 nakazuje prisotnost 
večjega deleža redkih alelov. Vrednosti  alelne raznoli-
kosti (ν) po posameznih lokusih so navedene v pregle-
dnici št. 4. Analiza hipotetične večlokusne gametske 
raznolikosti (ν
gam
) poskusnih dreves bukve je pokazala, 
da se število genetsko različnih 17 lokusnih gametskih 
tipov, ki bi jih lahko proizvedle skupine 50 vzorčnih 
dreves v populacijah, giblje v razponu vrednosti od 99,8 
(Kladje) do 203,1 (Brička) in ustreza razmerju 1:2,04. 
Čeprav imajo izračunane vrednosti samo nakazovalni 
značaj, ta primerjava nakazuje na večji potencial skupi-
ne podsajenih dreves bukve na lokaciji Brička kot pri 
skupini podsajenih dreves bukve na lokaciji Kladje za 
proizvodnjo genetsko različnih gamet, ki bodo v novi 
generaciji podvržene genetski variaciji. Povprečni vre-

20
G. BOŽIČ, L. KUTNAR & M. ZUPANČIČ: GENETIC VARIABILITY AND SUITABILITY OF UNDER-PLANTED BEECH IN SELECTED ...
FOLIA BIOLOGICA ET GEOLOGICA 52/1-2 – 2011
dnosti dejanske (opažene) heterozigotnosti (H
a
) za 17 
lokusni genski sklad sta v razponu od 21,1 % v skupini 
dreves Kladje do 23,5 % v skupini dreves Brička, kar 
ustreza razmerju 1:1,11. Stopnje heterozigotnosti se med 
testnima populacijama Brička in Kladje izrazito spre-
minjajo na 5 lokusih in sicer na Mdh-A (2 % vs. 20 %), 
Mnr-A (6 % vs. 26 %), Per-B (26 % vs. 48 %), Pgi-B (16 % 
vs. 2 %), Pgm-A (44 % vs. 18 %).
Genetsko variabilnost med osebki znotraj posame-
zne populacije, neodvisno od populacijske velikosti ozi-
roma števila proučevanih osebkov, opredeljujemo s sto-
pnjo genetske diferenciacije (δ
T
). V vzorčenih populaci-
jah podsajene bukve se povprečne stopnje genetske 
(alelne) diferenciacije δ
T
 gibljejo v razponu od 22,3 % 
(Kladje) do 25,6 % (Brička), kar ustreza razmerju 1:1,15. 
Opažene frekvence genotipov se pri večini lokusov uje-
majo s frekvencami genotipov, pričakovanimi po Har-
dy-Weinbergovem ravnotežju. Značilna odstopanja od 
Hardy-Weinbergove strukture smo na lokaciji Brička 
ugotovili na lokusih Mnr-A, Per-A, 6-Pgdh-B, na lokaciji 
Kladje pa na lokusih Aat-B, Per-A in Skdh-A. V vzorčeni 
populaciji Kladje je na lokusu Aat-B prišlo tudi do poja-
va značilnega primanjkljaja heterozigotov. Odstopanja 
pričakovanih genotipskih frekvenc od Hardy-Weinber-
gove strukture v skladu s Hardy-Weinbergovem zako-
nom nakazujejo, da je v populacijah lahko prišlo do dru-
gačnega prenosa genov kot pri panmiksični oplodnji ali 
pa so na testne populacije delovale različne oblike genet-
ske selekcije. Največja možna stopnja hetrozigotnosti 
(H
c
) je v vzorčenih populacijah realizirana od 77,9 % 
(Brička) do 84,0 % (Kladje). Izračunana vrednost (H
c
) za 
obe vzorčeni populaciji skupaj sicer nakazuje pomanj-
kanje heterozigotov v primerjavi z največjo dosegljivo 
vrednostjo, ki je enaka 100 %. Vendar zaradi pomanjka-
nja podatkov o izvoru matičnih sestojev bukve in prete-
klih razvojnih fazah v analizi zajetih skupin dreves, 
podsajenih v monokulture smreke na Pohorju, ne more-
mo ugotoviti, ali je na ta pojav vplival reproduktivni sis-
tem, način pridobivanja in rabe gozdnega reprodukcij-
skega materiala in / ali tudi različne oblike (preživetve-
ne) selekcije. 
Genetska diferenciacija med vzorčenima populacijama
 
Pogostosti posameznih alelov na nekaterih lokusih (npr. 
Pgm-A
2
 (9 % vs. 40 %), Per-B
1
 (11 % vs. 37 %), Mdh-B
4
 (5 
% vs. 16 %), Mdh-A
1
 (1 % vs. 10 %), 6-Pgdh-C
4
 (8 % vs. 
23 %)) deloma nakazujejo veliko različnost sestojev. Če 
primerjamo alelne porazdelitve vzorčeni populacij pod-
sajene bukve je verjetnost odklonov od homogenih alel-
nih struktur statistično značilna pri 5 od 17 analiziranih 
lokusov (preglednica 4). Izračunane vrednosti kažejo, da 
so odkloni od homogenosti alelnih  porazdelitev visoko 
značilni na lokusih Per-B in Pgm-A (α = 0,001), Mdh-A 
(α = 0,01), s stopnjo tveganja α = 0,05 pa tudi na Mdh-B 
in Pgi-B. Delež alelov, ki si jih testni populaciji med seboj 
ne delita (d
0
), za genski sklad 17 polimorfnih lokusov, v 
povprečju znaša 9,6 %. Na primeru posameznih lokusov 
ugotavljamo tudi visoke vrednosti genetskih razdalj. 
Vzorčeni skupini bukve, ki se na lokusu Pgm-A ločita v 
31 % alelnem in 44 % genotipskem deležu, na lokusih 
Per-B in Mdh-B pa v 29 % oz. 19 %  alelnem ter v 38 % oz. 
26 % genotipskem deležu, že dovoljujeta ugotovitev o 
večji genetski diferenciranosti med njima. Hipoteze, da 
imajo vzorčene skupine dreves bukve podsajene v dveh 
smrekovih monokulturah na Pohorju (Brička in Kladje), 
podobno populacijsko genetsko strukturo, v našem pri-
meru ne moremo potrditi.
Razprava
V izbranih smrekovih monokulturah na Pohorju ima 
populacija podsajene bukve na lokaciji Brička v genskem 
skladu večjo efektivno alelno raznolikost, hipotetično 
večlokusno gametsko raznolikost, opaženo heterozigo-
tnost ter večjo diferenciranost med osebki znotraj popu-
lacije kot populacija podsajene bukve na lokaciji Kladje. 
Razlogi za različne primerjalne vrednosti pri posame-
znih vzorčenih populacijah niso poznani. Ugotovljene 
razlike v stopnji genetske variabilnosti so lahko odraz 
razlik v izvoru provenienc, zgodovinskih razlik v pose-
gih v prostor na območju matičnih sestojev, razlik v na-
činih pridobivanja in rabe gozdnega reprodukcijskega 
materiala in / ali različne oblike preživitvene selekcije 
mladic bukve tako v matičnih kakor tudi v novih, spre-
menjenih razmerah njihovega življenjskega okolja. Seve-
da so to le teoretične predpostavke, ki v našem primeru 
niso bile preverjene. Priporočljivo bi bilo še dodatno 
raziskati genetske strukture sestojev bukve z naravnim 
mladjem, ki so preživela obdobje smrekovih monokul-
tur na območju Pohorja, da bi lahko spoznali, ali je bila 
v naši raziskavi analizirana genetska struktura vzorčene 
bukve sploh reprezentativna ali ne. 
Prvi dokaz o obstoječih genetskih razlikah med pre-
učevanima skupinama podsajene bukve na lokaciji Brič-
ka in Kladje podaja rezultat statističnega testa homoge-
nosti alelnih struktur na polimorfnih genskih lokusih. 
Med alelnima porazdelitvama vzorčenih populacij 
bukve smo dobili značilno različne odklone kar pri 5 od 
17 genskih lokusov. Stopnja analize genetske diferenci-
ranosti bukve je med vzorčenima populacijama soraz-
merno velika. Med skupinama podsajene bukve v izbra-
nih smrekovih monokulturah na južnem delu Pohorja je 
genetska diferenciacija (d
0
) izražena z deležem alelov, ki 

21
G. BOŽIČ, L. KUTNAR & M. ZUPANČIČ: GENETIC VARIABILITY AND SUITABILITY OF UNDER-PLANTED BEECH IN SELECTED ...
FOLIA BIOLOGICA ET GEOLOGICA 52/1-2 – 2011
si jih populaciji med seboj ne delita, 9,6 %. Ta vrednost je 
podobna ugotovljeni vrednosti alelne (genske) razdalje 
(d
0
; Gregorius 1974) med najbolj diferenciranimi po-
pulacijami bukve na Bavarskem (Nemčija), ki se med 
seboj sicer razlikujejo od 2,6 % do 10,9 % (Konnert & 
Henkel 1997). Podobne visoke vrednosti genetske dife-
renciacije, ki so jih ugotovili med štirimi populacijami z 
najbolj različnih rastišč, navaja tudi raziskava dvajsetih 
domnevno avtohtonih populacij bukve iz območja za-
hodne Nemčije (Turok 1994). 
Opažena odstopanja med vzorčenima populacijama 
Brička in Kladje na Pohorju bi lahko v primeru repre-
zentativnosti genetskih struktur preučevanih populacij 
nakazovala, da je bil pretok genov med matičnimi sesto-
ji bukve omejen ali pa, da je večja genetska diferencira-
nost lahko tudi posledica izolacije in specifičnih selek-
cijskih procesov, ki jih je doživela bukev na teh lokacijah. 
Kar nadalje lahko pomeni tudi, da saditveni material, ki 
je bil podsajen v smrekovih monokulturah Brička in 
Kladje, ne prihaja iz istega matičnega izvora bukve. Dej-
stvo pa je, da vseh teh povezav ni mogoče podrobneje 
spoznati ter oceniti njihovih vplivov brez novih poglo-
bljenih raziskav. Rezultati naših preučevanj zato naka-
zujejo na sklep, da je skupina dreves bukve v smrekovi 
monokulturi Brička genetsko nekoliko različna od sku-
pine dreves bukve v smrekovi monokulturi Kladje. 
Pri podsadnjah bukve v smrekovih monokulturah 
(brez vključevanja naravnega pomlajevanja bukve) ob-
staja stalna nevarnost za izgubo alelov (oz. genetske in-
formacije) zaradi genetskega zdrsa, ki bi lahko nastal v 
majhnih izoliranih populacijah zaradi zmanjševanja pr-
votne velikosti populacij pri razvoju in rasti bodočega 
sestoja bukve. Ta nevarnost je v našem primeru potenci-
alno večja za populacijo bukve Kladje, ki nakazuje nižjo 
stopnjo genetske variabilnosti znotraj populacije in ima 
večji delež redkih alelov (s frekvencami <  5 %) kot po-
pulacija bukve Brička. 
Zasnova bodočega gozda je kritična faza v življenju 
gozda. Za obnovo gozdov je zato priporočljivo uporabiti 
naravno pomlajevanje sestojev. V primerih, kjer to ni 
mogoče, pa uporabo semenskega materiala in puljenk 
pridobljenih iz odobrenih semenskih sestojev. To je v ti-
stih semenskih objektih, ki jih skladno z določbami Za-
kona o gozdnem reprodukcijskem materialu ULRS, št. 
58/02, 85/02, 45/04) odobri Gozdarski inštitut Slovenije 
in so vpisani v Register gozdnih semenskih objektov 
(ULRS, št. 91/03). »Za večinske drevesne vrste (predvsem 
za bukev, dob, graden, jelko in smreko) se priporoča upo-
raba semena in sadik v okviru višinskega pasu in prove-
nienčnega območja, iz katerega izhaja, ali iz sosednjega 
območja. Manj priporočljiva je uporaba semena in sadik 
iz drugih provenienčnih območij, le izjemoma gozdar 
oz. gojitelj predpiše tudi uporabo semena in sadik iz so-
sednjih višinskih pasov. Za manjšinske drevesne vrste 
velja, da je vsa Slovenija enotno provenienčno območje, 
razdeljeno na 4 višinske pasove. Kljub temu je tudi za te 
vrste priporočljiva uporaba semena v območju, iz katere-
ga izvira« (Medved s sod. 2011, str. 137). Gozdno seme je 
genetski material, zato ima izbor gozdnih semenskih 
virov zelo daljnosežne posledice. Kakovostnih semen-
skih virov oziroma sestojev zaradi splošne spremenjeno-
sti gozdov ni veliko in jih je zaradi sedanje antropogene 
obremenjenosti gozdov vedno manj. Kot porazdelitev 
tveganja in kot pogoj za ekološko prilagodljivost gozda 
morajo gozdni semenski viri zajemati dovolj veliko bio-
loško raznovrstnost, to je vse pomembnejše drevesne 
vrste z njihovimi krajevnimi rasami in njihovo genetsko 
variabilnostjo. To je še posebej pomembno ob sedanjem 
naglem spreminjanju podnebja in drugih antropogeno 
povzročenih nepredvidljivostih. Biološko raznovrstnost 
in njeno prilagojenost krajevnim ekološkim razmeram 
še najprej lahko pričakujemo v gozdovih z dobro ohra-
njeno naravnostjo in avtohtonostjo. 
Za pridobivanje gozdnega reprodukcijskega materi-
ala je v pohorskem provenienčnem območju odobren le 
en semenski sestoj in sicer provenienca Osankarica 
(ident. številka GSO: 2.0119) na nadmorski višini 1240 
m, kategorija »izbran« (Kraigher, Božič & Verlič 
20 1 1 ). T a semenski sestoj je predlagan tudi za gozdni 
genski rezervat v Sloveniji in za enoto dinamičnega var-
stva genov na ravni Evrope (Westergren, Božič & 
Kraigher 2010). Za potrebe premene smrekovih mono-
kultur na Pohorju se uporabljajo tudi puljenke, nabrane 
v semenskem sestoju kategorije »izbran« (ident. številka 
GSO: 4.0175, provenienca Temenjak) v sosedstvu  (Kra-
igher, Božič & Verlič 2011). Odobreni semenski sestoj 
na nadmorski legi od 650 m do 700 m uvrščamo v Sa-
vinjsko-Šaleško ekološko podregijo (koda 4.3) Predalp-
skega provenienčnega območja (Kutnar s sod. 2002).
Na Pohorju je razmeroma malo ohranjenih bukovih 
gozdov. Večina le teh je spremenjena v smrekove mono-
kulture. Poleg tega je Pohorje poraščeno z naravnimi 
smrekovimi gozdovi, zlasti v višjih nadmorskih legah, 
to je v altimontanskem in nižjem subalpinskem pasu. 
Montanski pas pa poraščajo jelovi gozdovi. Naravne 
možnosti ohranjene genetske dediščine bukve so povr-
šinsko omejene, na teh površinah pa je struktura sesto-
jev razmeroma slaba. Bukovi semenovci so redki, več je 
panjevcev ali mešanih sestojev panjevca in semenovca. 
Ne glede na sestojno obliko bi bilo potrebno kolikor to-
liko ustrezne sestoje dodatno izbrati za semenske sesto-
je, čeprav morda površinsko zelo omejene. Dodatne se-
menske sestoje lahko izberemo v pohorskem proveni-
enčnem območju ali v podobnih ekoloških razmerah v 
sosednjih provenienčnih območjih (alpskem in predalp-
skem). V vseh primerih gre za sestoje, ki jih uvrščamo v 

22
G. BOŽIČ, L. KUTNAR & M. ZUPANČIČ: GENETIC VARIABILITY AND SUITABILITY OF UNDER-PLANTED BEECH IN SELECTED ...
FOLIA BIOLOGICA ET GEOLOGICA 52/1-2 – 2011
asociacije (sintaksone) Luzulo-Fagetum Meusel 1937, 
Hieracio rotundati-Fagetum Ž. Košir 1994 in Cardamine 
savensi-Fagetum Ž. Košir 1962 var. geogr. Abies alba Ž. 
Košir 1994 v montansko / altimontanskem pasu ter v 
asociacije (sintaksone)  Castaneo-Fagetum sylvaticae 
Marinček & Zupančič (1979) 1995 in Hedero-Fagetum Ž. 
Košir (1962) 1994 var. geogr. Polystichum setiferum Ž. 
Košir 1994 v kolinskem pasu. 
Predlagamo razširitev mreže semenskih objektov 
na Pohorju (vključno z Rdečim bregom) in Kobanskem 
s ciljem izkoriščanja obstoječih potencialov bukve, ki je 
preživela obdobje smrekovih monokultur za potrebe ob-
nove teh kompleksov z uporabo rastišču prilagojenega 
sadilnega materiala. Pomembnost tega ukrepa je v pri-
pravi kvalitetne baze saditvenega materiala primernega 
za podsadnjo bukve v smrekove monokulture na Pohor-
ju, ob hkratnem ohranjanju prilagoditvenega potenciala 
za rast in razvoj  bukve na ustreznih površinah degradi-
ranih gozdov v luči možnih podnebnih sprememb. Go-
spodarsko zanimivi iglavci, kot sta smreka in jelka, 
imajo razmeroma velik delež v lesni zalogi zelo različnih 
g o zdnih združb v S l o v e ni j i. V e n dar p a j e po vrš ins ki 
delež potencialnih združb, v katerih so iglavci prevladu-
joči, razmeroma majhen. Kot kažejo napovedi modela, 
se bo verjetno ta delež še dodatno zmanjšal. Tako kot 
ugotavljajo za zahodno in srednjo Evropo (Kienast, Br-
zeziecki & Wildi 1998; Lexer s sod. 2002, Maracchi, 
Sirotenko & Bindi 2005; Koca, Smith & Sykes 2006), 
lahko pričakujemo tudi pri nas, da bo prišlo do izrazite 
zamenjave gozdov iglavcev z gozdovi listavcev (Kutnar, 
Kobler & Bergant 2009; Kutnar & Kobler 2011). Si-
mulacije podnebnih učinkov na smreko nakazujejo iz-
razit upad deleža in slabše perspektive te vrste ob ure-
sničitvi splošno veljavnih podnebnih scenarijev, ki pred-
videvajo nadaljnje segrevanje ozračja v prihodnosti 
(Ogris & Jurc 2010, Kobler & Kutnar 2010). 
Problematika semenskih virov bukve na Pohorju 
zato zasluži še posebno pozornost. Delo pri ohranjanju 
semenskih virov in biološke raznovrstnosti gozda naj 
vključuje tako zavarovanje semenskih virov s pomočjo 
zakonodaje in predpisov, kot zavarovanje semenskih 
virov s statusom gozda s posebnim namenom in druga 
gozdarska naravovarstvena prizadevanja za ohranjanje 
naravne genetske dediščine z zavarovanjem in dopolnje-
vanjem mreže gozdnih genskih rezervatov in drugih 
površin s pomembnimi semenskimi viri. Smiselno je 
tudi nadaljevati z neposredno uporabnimi raziskavami 
in razvojnim delom za potrebe gozdnega semenarstva in 
drevesničarstva vključno s poglobljenimi raziskavami 
genetskih značilnosti populacij gozdnih drevesnih vrst 
v Sloveniji. 
Zaključki
Na osnovi rezultatov analiz genetske strukture podsaje-
ne mlade bukve v izbranih smrekovih monokulturah na 
Pohorju z izoencimskimi genskimi označevalci sklepa-
mo: 
• Podsajene bukve na lokaciji Brička so genetsko ne-
k o l i k o r a z l i č n e o d p o d s a j e n i h b u k e v n a l o k a c i j i 
Kladje. 
• Genetska variabilnost podsajenih bukev znotraj po-
samezne populacije je po kazalcih genetske raznoli-
kosti (H
a
, ν, ν
gam
, δ
T
) večja na lokaciji Brička kot pa 
na lokaciji Kladje.
• V populaciji bukve na lokaciji Kladje obstaja večja 
potencialna nevarnost za izgubo genetske informa-
cije (alelov) zaradi genetskega zdrsa, ki bi lahko na-
stal v manjših izoliranih populacijah pri razvoju 
bodočega sestoja (kot v populaciji na lokaciji Brič-
ka).
• Alelna (genska) razdalja med podsajeno bukvijo na 
lokaciji Brička in Kladje, ki smo jo izračunali po 
Gregorius (1974) je za preučevani genski sklad so-
razmerno velika (d
0
 =  9,6 %).
• Problematika semenskih virov bukve na Pohorju 
zasluži posebno pozornost. Potrebno je poiskati 
razmeroma ohranjene bukove sestoje na čim bolj 
različnih rastiščih na Pohorju in Kobanskem, ki bi 
potencialno lahko bili izbrani kot semenski sestoji. 
ACKNOWLEDGMENTS
The research took place partially within the framework 
of the research tasks of projects Designation of measures 
to ensure genetic-based forest protection (V1-1140), 
Carbon dynamics in natural beech sites (L4-6232) and 
Programme Group for Forest Ecology, Biology and Te-
chnology (P4-0107). We produced the recommendation 
of enlargement of the network of forest seed objects wi-
thin the framework of tasks of the Public Forestry Servi-
ce. Particular thanks are due to Dr. Monika Konnert 
(ASP, Teisendorf) for all her help in work in the genetics 
laboratory and Prof. Dr. Hojka Kraigher (SFI, Ljubljana) 
for a critical review of the content of the paper and expert 
advice. Thanks also to Barbara Štupar and Sussana 
Nowak.

23
G. BOŽIČ, L. KUTNAR & M. ZUPANČIČ: GENETIC VARIABILITY AND SUITABILITY OF UNDER-PLANTED BEECH IN SELECTED ...
FOLIA BIOLOGICA ET GEOLOGICA 52/1-2 – 2011
REFERENCES - LITERATURA
Abildtrup, J., J. Riis & B. Jellesmark-Thorsen, 1997: The reservation price approach an informationally efficient 
markets. Journal of Forest Economics (3): 229-246.
Anonymous, 2002. Zakon o gozdnem reprodukcijskem materialu. Urad. list Repub. Slov. (1991), 58/02, 85/02, 45/04.
Anonymous, 2003. Pravilnik o pogojih za odobritev semenskih objektov v kategorijah “znano poreklo” in “izbran”, ter 
o seznamu gozdnih semenskih objektov. Urad. list Repub. Slov. (1991), 91/03.
Bradshaw, R.H.W., B.H., Holmqvist, S.A. Cowling & M.T. Sykes, 2001. The effects of climate change on the distri-
bution and management of Picea abies in southern Scandinavia. Can. J. For. Res., 30: 1992-1998.
Breznikar, A., G. Mlinšek, M. Cehner, Z. Grecs & M. Čater, 2006. Strategije sanacije antropogenih smrekovih se-
stojev na Pohorju. V: Simončič, P. & M. Čater (ur.): Splošne ekološke in gozdnogojitvene osnove za podsadnjo 
bukve (Fagus sylvatica L.) v antropogenih smrekovih sestojih.  Studia Forestalia Slovenica (Ljubljana) 129: 143-153.
Budnar-Tregubov, A., 1958. Palinološko raziskovanje barij na Pokljuki in Pohorju. Geologija, Razprave in poročila 
(Ljubljana) 4: 197-220.
Čater, M., 2011. Morfološki in fiziološki odziv mladih bukev (Fagus sylvatica L.) na svetlobo v naravnih bukovih sesto-
jih Slovenije. Les (Ljubljana) 63 (5): 188-191.
Culiberg M. & Šercelj, A., 2000. Spremembe prvotnih gozdov na Pohorju v zadnjih stoletjih z vidika pelodne analize. 
Razprave, 4. r., SAZU (Ljubljana) 3: 3-39.
Dakskobler, I., 2008. Pregled bukovih rastišč v Sloveniji. Zb. gozd. lesar. (Ljubljana) 87: 3-14.
Diaci, J. & Z. Grecs, 2003. Uspešnost gojenja gozdov v zadnjem desetletju in priložnosti za prihodnost. In: Bončina, 
A. (ed.). Območni gozdnogospodarski načrti in razv ojne perspektive slovenskega gozdarstva. Collection of papers, 
BF, Department of Foresty and Renewal of Forest Resources (Ljubljana): 81-102.
Diaci, J., 2006. Petdeset let premen drugotnih smrekovih gozdov v Sloveniji. In: Simončič P. & M. Čater (ed.): Splošne 
ekološke in gozdnogojitvene osnove za podsadnjo bukve (Fagus sylvatica L.) v antropogenih smrekovih sestojih. 
Studia Forestalia Slovenica (Ljubljana) 129: 56-67.
Finkeldey, R., 1993. Die Bedeutung allelischer Profile fuer die Konservierung genetischer Ressourcen bei Waldbaeu-
men. Goett. Forstgenet. Bericht (Goettingen) 14.
Gillet, E. M., 1998. GSED – Genetic Structures from Electrophoresis Data. Version 1.1, Institut fuer Forstgenetik und 
Forstpflanzenzuechtung, Universitaet Goettingen (Goettingen).
Grabherr, G. & G. Koch, 1993. Wie naturnah ist de Österreichische Wald? Österr. Forstzeitung (Wien) 11: 57-58.
Gregorius H. R., J. Krauhausen J. & G. Mueller-Starck, 1986. Spatial and temporal genetic differentiation among 
the seed in a stand of Fagus sylvatica L. Heredity 57: 255-262.
Gregorius, H. R., 1974. Genetischer Abstand zwischen Populationen. I. Zur Konzeption der genetischen Abstands-
messung. Silvae Genetica, (Frankfurt a. M.) 23: 22-27.
Gregorius, H. R., 1978. The concept of genetic diversity and its formal relationship to heterozygosity and genetic dis-
tance. Mathematical Biosciences 41 (3-4): 253–271.
Gregorius, H. R., 1987. The relationship between the concepts of genetic diversity and differentiation. Teor. Appl. 
Genet. 74 (3): 397-401.
Hannah, L., J.L. Carr, & A. Lankerani, 1995. Human disturbance and natural habitat: A biome level analysis of a 
global data set. Biodiv. Conserv. 4: 128-155.
Johann, E., M. Agnoletti, A-L. Axelsson, M. Bürgi, L. Östlund, X., Rochel, U.E. Schmidt, A. Schuler, J-P. 
Skovsgaard & V. Winiwarter, 2004. History of secondary Norway spruce forests in Europe. In: Spiecker, H, J. 
Hansen, E. Klimo, J. P. Skovsgaard, H. Sterba & K. V . Teuffel (ed.): Norway spruce conversion - options and 
consequences. European Forest Institute Research Report 18 (Brill NV, Leiden, Boston): 25-62.
Kienast, F., B. Brzeziecki & O. Wildi, 1998. Potential impacts of climate change on species richness in mountain 
forests an ecological risk assessment. Biological Conservation 83: 291-305.
Kobler, A. & L. Kutnar, 2010. Potential forest change in Slovenia due to climate change. In: Medved, M. (ed.). Small 
scale forestry in a changing world: opportunities and challenges and the role of extension and technology tran-
sfer. Proceedings of the conference. Slovenian Forestry Institute, Slovenia Forest Service (Ljubljana): 333-341.
Koca, D., S. Smith & M.T. Sykes, 2006. Modelling regional climate change effects on potential natural ecosystems in 
Sweden. Climatic Change 78: 381-406.
Konnert, M. & W. Henkel, 1997. Untersuchungen zur genetischen Variation der Buche (Fagus sylvatica L.) in Thue-
ringen. Allgemeine Forst-und Jagdzeitung, 168 (10): 128-190. 

24
G. BOŽIČ, L. KUTNAR & M. ZUPANČIČ: GENETIC VARIABILITY AND SUITABILITY OF UNDER-PLANTED BEECH IN SELECTED ...
FOLIA BIOLOGICA ET GEOLOGICA 52/1-2 – 2011
Konnert, M., E. Hussendoerfer & A. Dounavi, 2004. Handbücher für Isoenzymanalyse. Anleitung fuer Isoen-
zymuntersuchung bei Buche (Fagus sylvatica). URL: (http://blag-fgr.genres.de/fileadmin/SITE_GENRES/down-
loads/docs/BLAG/buche-arbeitsanleitung.pdf).
Košir, Ž., M. Zorn-Pogorelc, J. Kalan, L. Marinček, I. Smole, L. Čampa, M. Šolar, B. Anko, M. Accetto, D. 
Robič, In. Toman, L. Žgajnar & N. Torelli, 1974. Gozdnovegetacijska karta Slovenije. 1:100.000. Biro za gozdar-
sko načrtovanje, zemljevid na 7 listih + legenda
Kraigher, H., G. Božič & A. Verlič, 2011. Seznam gozdnih semenskih objektov - stanje na dan 1. 1. 2011. Urad. list 
Repub. Slov. (1991), 28.1.2011, 6, 208, 597-603.
Kutnar, L. & A. Kobler 2011. Prediction of forest vegetation shift due to different climate-change scenarios in Slove-
nia. Šumarski list (Zagreb) 135 (3-4): 113-126.
Kutnar, L., A. Kobler & K. Bergant, 2009. Vpliv podnebnih sprememb na pričakovano prostorsko prerazporeditev 
tipov gozdne vegetacije. Zbornik gozdarstva in lesarstva (Ljubljana) 89: 33-42.
Kutnar , L., M. Zupančič,  D. Robič,  N. Zupančič , S. Žitnik , T. Kralj, I. Tavčar, I., M.  Dolinar, C. Zrnec, & H. 
Kraigher, 2002. Razmejitev provenienčnih območij gozdnih drevesnih vrst v Sloveniji na osnovi ekoloških regij . 
Zbornik gozdarstva in lesarstva (Ljubljana) 67: 73-117.
Larsen, J.B., 1995. Ecological stability of forests and sustainable silviculture. Forest Ecology and Management 73 (1-3): 
85-96.
Lexer, M. J., K. Hönninger, H. Scheifinger, Ch. Matulla, N. Groll, H. Kromp-Kolb, K. Schadauer, F. Star-
linger & M. Englisch, 2002. The sensitivity of Austrian forests to scenarios of climatic change: a large-scale risk 
assessment based on a modified gap model and forest inventory data. Forest Ecology and Management 162: 
53-72.
Löf, M., 2000. Establishment and growth in seedlings of Fagus sylvatica and Quercus robur: influence of interference 
from herbaceaous vegetation. Can. J. For. Res. 30: 855-864.
Maracchi, G., O. Sirotenko & M. Bindi, 2005. Impacts of present and future climate variability on agriculture and 
forestry in the temperate regions: Europe. Climatic Change 70: 117-135.
Mattsson, L. & C.Z. Li, 1994. How do different forest management-practices affect the non-timber value of forests – an 
economic analysis. Journal of Environmental Management 41:79-88.
Medved, M, M. Bajc, G. Božič, M. Čas, M. Čater, A. Ferreira, T. Grebenc, M. Kobal, H. Kraigher, L. Kut-
nar, B. Mali, Š. Planinšek, P. Simončič, M. Urbančič, U.Vilhar, M. Westergren, N. Krajnc, G. Kušar, T. 
Levanič, S. Poljanšek, D. Jurc, M. Jurc, N. Ogris, J. Klun, T. Premrl, R. Robek, P. Železnik, J. Gričar & 
Piškur, M., 2011. Gospodarjenje z gozdom za lastnike gozdov. Kmečki glas, Ljubljana.
Mlinšek, D., 1955. Ureditveni načrt za gospodarsko enoto Mislinja . Gozdno gospodarstvo Slovenj Gradec.
Nei, M. 1973. Analysis of gene diversity in subdivided populations. Proc. Nat. Acad. Sci. USA, 70: 3321-3323.
Ogris, N. & M. Jurc, 2010. Sanitary felling of Norway spruce due to spruce bark beetles in Slovenia: A model and pro-
jections for various climate change scenarios. Ecological Modelling, 221: 290–302.
Otto, H.-J., 1994. Waldökologie. Ulmer. Stuttgart.
Šercelj, A. 1996. Začetki in razvoj gozdov v Sloveniji. Opera 35, Ljubljana.
Spellmann, H. & S. Wagner, 1993. Aids to decision making for planning regeneration in Norway spruce stands with 
advance planting of beech in the Harz Mountains. Forst-und-Holz (Hannover) 48 (17): 483-490.
Spiecker, H. 2000. The growth of Norway spruce within and beyond its natural range. V:  Hasenauer, H. (ur.): Pro-
ceedings from IUFRO international conference on Forest Ecosystem Restoration. Wienna, Austria 10-12 April 
2000. Institute for forest growth research (Wien): 247-256.
Stanturf, J.A. & P. Madsen, 2002. Restoration concepts for temperate and boreal forests of North America and We-
stern Europe. Plant Biosystems 136: 143-158.
Teuffel, K. V., B. Heinrich & M. Baumgarten, 2004. Present distribution of secondary Norway spruce in Europe. 
In: Spiecker, H., J. Hansen, E. Klimo, J. P. Skovsgaard, H. Sterba & K. V. Teuffel (ed.): Norway spruce con-
version - options and consequences. European Forest Institute Research Report 18 (Brill NV, Leiden, Boston): 
63-96.
Turok, J. 1994. Levels of genetic variation in 20 beech (Fagus sylvatica L.) populations from Western Germany. Mit-
teilungen der Bundesforschunganstalt Hamburg (Hamburg).
Urbančič, M., & L. Kutnar, 2006 . Site conditions of the Brička plot and comparisons with other SUSTMAN plots. In: 
Simončič, P. & M. Čater (ed.): Splošne ekološke in gozdnogojitvene osnove za podsadnjo bukve (Fagus sylvatica 
L.) v antropogenih smrekovih sestojih.  Studia Forestalia Slovenica (Ljubljana) 129, 68-85.

25
G. BOŽIČ, L. KUTNAR & M. ZUPANČIČ: GENETIC VARIABILITY AND SUITABILITY OF UNDER-PLANTED BEECH IN SELECTED ...
FOLIA BIOLOGICA ET GEOLOGICA 52/1-2 – 2011
Westergren, M., G. Božič & H. Kraigher, 2010. Tehnične smernice za ohranjanje in rabo genskih virov : bukev : 
Fagus sylvatica : Slovenija. Gozd. vestn. (Ljubljana) 68 (2): 103-106.
Zerbe, S., 2002. Restoration of natural broad-leaved woodland in Central Europe on sites with coniferous forest plan-
tations. For. Ecol. Manage. 167: 27-42.