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Dugotrajne će suše u budućnosti dodatno opteretiti šumske ekosustave smanjujući njihovu produktivnost i sveukupnu bioraznolikost što bi moglo rezultirati izmjenom omjera vrsta u mješovitim šumskim sastojinama diljem Europe. Hrast kitnjak bi u odnosu na običnu bukvu mogao postati daleko konkurentniji, zbog dubljeg zakorijenjivanja, kseromorfnije strukture lišća i brzog oporavka asimilacije CO2 nakon popuštanja suše. Pod utjecajem klimatskih promjena u posljednjih 20-ak godina na području Europe dolazi do ometanja uredne ishrane šumskoga drveća s fosforom (P) na što ukazuje opadanje koncentracije P u lišću. Iako istraživanje fiziološke uloge P u metabolizmu šumskoga drveća trenutno predstavlja „state of the art“ problematiku, u literaturi je slabo zastupljena njegova uloga u sušnom stresu šumskoga drveća. Genetska raznolikost i unutarvrsne adaptivne varijacije u odgovoru na sušu kod obje vrste na području jugoistočne Europe do sada nisu bile istraživane. Optimalna ishranjenost šumskoga drveća s P mogla bi podići njihovu toleranciju prema suši jer P regulira fotosintezu i glikolizu te na taj način kontrolira asimilaciju CO2 i kasniju upotrebu ugljikohidrata za produkciju biomase. Optimalna ishranjenost s P pozitivno utječe i na sposobnost zaštite i popravka oštećenog fotosintetskog aparata uslijed pojave oksidacijskog stresa izazvanoga sušnim stresom. Obična bukva i hrast kitnjak diljem Europe tvore mješovite šumske zajednice koje pridolaze na cijelom spektru šumskih tala koja se odlikuju različitom vlažnošću i koncentracijama lakopristupačnog P u tlu. Ciljevi ovoga projekta (kojega financira Hrvatska zaklada za znanost) su utvrditi: (i) utjecaj povišene koncentracije P u tlu na toleranciju obične bukve i hrasta kitnjaka prema sušnom stresu, (ii) postojanje lokalne adaptiranosti provenijencija obične bukve i hrasta kitnjaka na sušni stres, kao i genotipskih razlika u toleranciji na sušu pod utjecajem povišene koncentracije P u tlu i (iii) postojanje tzv. memorijskih efekata kod obične bukve i hrasta kitnjaka nakon pretrpljenog sušnog stresa te utjecaj povišene koncentracije P u tlu na takve efekte.

European black poplar (Populus nigra L.) is a pioneer species that belongs to the Salicaceae family and occurs in riparian ecosystems. It is one of the most endangered forest species in its entire distribution area. In Croatia, black poplars are considered an economically important forest species, but mostly clones originate from crossing combinations with American and European black poplar (Populus × canadensis Moench), while a small number of clones are native black poplar. Studies on native black poplar are quite rare and the generative propagation has not been used. The aim of this study was to gain knowledge on the production of high-quality black poplar seedlings and to carry out the selection of genotypes with the aim of establishing a base for future breeding. The female black poplar tree was selected on phenotypic characteristics in the area of Forest Administration Osijek, Forest Office Valpovo. The tree was cut down in April 2019, and branches with half-open seed capsules on catkins were collected. The branches were transferred to the Croatian Forest Research Institute’s greenhouse, where the catkins opened under the influence of the high temperature. Sowing was done in different substrates to test their effectiveness. Black poplar seedlings were selected and transplanted with regard to development and height growth. The results showed differences in height growth between plants sown in two different substrates and the occurrence of fungal diseases only on plants sown in pure sand. With subsequent multiple propagation using cuttings and selection by genotype, it is expected that it will be possible to identify several clones of native black poplar that will be introduced for use in forestry in Croatia. The use of quality plants grown from seeds will increase the genetic diversity and preserve the native black poplar gene pool.

This research was conducted on four-year-old saplings of common beech and sessile oak originating from two mature mixed beech-oak stands from the Republic of Croatia (RH), which are characterized by similar orographic and edaphic (chemical composition and mechanical soil structure) conditions. In addition, both stands belong to the same phytosociological association, Epimedio-Carpinetum betuli (Horvat 1938) Borhidi 1963. However, during the development of the studied saplings in the period from 2016 to 2020, stands from north-western part of the RH near Karlovac (KA) were more frequently exposed to drought periods than stands from eastern part of RH near Slavonski Brod (SB). Therefore, the aim of this study was to examine the impact of drought on the functional adaptation of growth and dry mass production of common beech and sessile oak saplings. Differences between stands (KA vs. SB) and species (beech vs. oak) were examined using two-factorial ANOVA with respect to a growth and dry mass production parameters, including their allometric relationships. According to the obtained results, the saplings from the KA stand had a thicker and lower stem, rooted deeper, and had a higher dry mass of coarse and fine roots compared to the saplings from the SB stand. This indicates that the saplings from the KA stand could be functionally more adapted to the drought habitat than the saplings from the SB stand due to more frequent exposure to drought periods. Such a result could be the consequences of different phenotypic modifications (drought reactions) and/or actual genetic differences between the studied stands, which could not be more accurately distinguished on this occasion. Furthermore, sessile oak saplings rooted deeper and had a higher dry mass of coarse roots than the common beech saplings that rooted shallower and had a higher dry mass of fine roots. This result corresponds to the previous knowledge on pattern of functional adaptation of sessile oak and common beech to moisture and/or dryness of the habitat, which differs in that sessile oak is oriented to absorb water from deeper soil layers by taproot, while common beech is oriented to absorb precipitation water from shallower layers of soil by fine roots.

This research was conducted on five-year-old saplings of common beech (Fagus sylvatica L.) and sessile oak (Quercus petraea /Matt./ Liebl.) originating from two mature mixed beech-oak stands from the Republic of Croatia. One stand is from the area of Slavonski Brod and one from the area of Karlovac. These two provenances are characterized by similar orographic and edaphic (chemical composition and mechanical soil structure) conditions, but differ in climate, especially in precipitation. In Slavonski Brod provenance average total annual precipitation is 770 mm (dry provenance) and in Karlovac provenance 1112 mm (wet provenance). During 2021, after the establishment of field trial, the saplings grew into two types of substrates. One type of substrate was a treatment with an increased phosphorus concentration (+P) and another type of substrate was a treatment with a lower phosphorus concentration (-P). The aim of this study was to examine the influence of different phosphorus concentrations in the substrate on leaves functional traits (phosphorus concentration in leaves, leaf dry matter content (LDMC), leaf mass per area (LMA), etc.) in beech and oak saplings originating from dry and wet provenance. The results showed that in the +P treatment there was a significant increase in the concentration of phosphorus in the leaves of both species originated from both provenances. However, LDMC and LMA in the +P treatment were significantly higher than the -P treatment in common beech, while LDMC and LMA in sessile oak were the same in both treatments. Saplings originating from dry provenance had a significantly higher LDMC and LMA than saplings from wet provenance. Research has shown that different phosphorus concentrations have different effects on the functional traits leaves depending on the species and provenance.

This research was conducted on a four-year-old common beech and sessile oak saplings originating from two mature mixed common beech and sessile oak stands (provenance) from the Republic of Croatia (HR). Provenances differ in annual amount of precipitation, which in provenance Slavonski Brod (SB) from the eastern part of the HR is about 770 mm (dry provenance), and in Karlovac (KA) from the north-western part of the HR is about 1112 mm (wet provenance). During year 2021, after the establishment of the experimental trail, the transplanted saplings grew into two soil types, one was characterized by high (0.30 g P2O5/l soil) and the other by low (0.16 g P2O5/l soil) phosphorus (P) concentration. The aim of this study was to examine the effect of higher soil P concentration on the average onset of spring bud burst and autumn leaf senescence in beech and oak saplings. The results showed that the onset of bud burst and leaf senescence in beech compared to oak saplings occurred significantly earlier, in six and ten days, respectively. Differences in the onset of bud burst and leaf senescence between oak provenances were not significant, whereas these differences between beech provenances were significant. Therefore, the onset of bud burst and leaf senescence in beech of dry SB provenance compared to wet KA provenance occurred earlier in five and three days, respectively. The higher soil P concentration significantly affected only the onset of leaf senescence in beech saplings. This means that the onset of leaf senescence in beech saplings under the higher compared to lower soil P concentration occurred three days earlier in the dry SB provenance and four days earlier in the wet KA provenance.

This research was conducted on a five-year-old common beech and sessile oak saplings originating from two mature mixed common beech and sessile oak stands (provenance) from the Republic of Croatia (HR). Provenances differ in annual amount of precipitation, which in provenance Slavonski Brod (SB) from the eastern part of the HR is about 770 mm (dry provenance), and in Karlovac (KA) from the north-western part of the HR is about 1112 mm (wet provenance). During year 2021, after the establishment of the experimental trail, the transplanted saplings grew into two soil types, one was characterized by high (0.30 g P2O5/L soil = +P tretment) and the other by low (0.16 g P2O5/l soil = -P treatment) phosphorus (P) concentration. In September 2021, the saplings of both species in the +P treatment had a higher concentration of P in the leaves than the sampligs from the -P treatment. The aim of this study was to examine the effect of different soil P concentration and/or phosphorus nutrition on the leaf dry matter content (LDMC = dry leaf mass/fresh leaf mass) and leaf mass per area (LMA = dry leaf mass/leaf area) of common beech and sessile oak saplings originated from dry and wet provenances. Results of factorial ANOVA with main effects of treatment (+P vs -P), provenences (dry BS vs. wet KA) and species (common beech vs. sessile oak) indicate that LDMC and LMA in +P treatment were significantly higher than in -P treatment, dry SB and wet KA provenance had similar LDMC and LMA, whilest the common beech had significantly lower LDMC and LMA than the sessile oak. Significant interaction between main effects ”treatment x species” indicate thad LDMC and SLA of sessile oak were similar in both +P and -P treatments, whilest LDMC and SLA of common beech in -P treatment were significantly lower than in +P treatment.

The potential of the CCM-200 chlorophyll meter for providing accurate estimates of total nitrogen concentrations was studied from 2009 to 2011 using pedunculate oak (Quercus robur L.) leaves collected in a field trial near Zagreb, Croatia. A fertilization treatment carried out in early spring 2009 and in variable weather conditions caused between-year differences in acorn yield and production of second and third flush shoots. A total of 10 linear calibration equations were constructed based on data from leaves sampled in early July (first flush leaves), in mid-August (second flush leaves) and in mid-September (first and second flush leaves). These equations reliably described (p < 0.001) the relationships between chlorophyll content index values (CCI) measured by the chlorophyll meter and leaf nitrogen concentration (LNC) with respect to the year and month of sampling. The results suggest that variable seasonal dynamics of LNC are influenced by second and/or third flushes as well as by acorn yield. This finding has negative consequences for applying the chlorophyll meter as a suitable tool for LNC assessments during a growing season or over several growing seasons. However, the chlorophyll meter still proved to be a potentially useful tool for LNC estimations, but only when calibration equations were constructed based on the first flush leaves sampled in mid-September (in the last third of a growing season).

U Hrvatskoj se na plantažama i kulturama topole uzgajaju klonovi nastali križanjem američke i europske crne topole (Populus x canadensis Moench) odnosno klonovi američke crne topole (Populus deltoides Bartr ex Marsh). Trenutno u našoj zemlji ne raspolažemo niti s jednim priznatim klonom autohtone crne topole (Populus nigra L.) Europska crna topola, kao jedna od najznačajnijih vrsta drveća u poplavnim šumama Hrvatske, ujedno je i jedna od ugroženijih vrsta na cijelom području svoje rasprostranjenosti. Gubitkom i fragmentacijom pogodnog staništa zbog hidromelioracijskih zahvata, te unošenjem i širenjem alohtonih vrsta, genetsko bogatstvo domaće crne topole je ugroženo. Stoga smo odlučili započeti s oplemenjivanjem ove vrste radi pridobivanja produktivnih klonova koji bi se mogli koristiti za osnivanje kultura i plantaža, a da pri tome ne ugrožavaju genofond autohtone vrste. Na području Uprave šuma podružnica Osijek, šumarija Valpovo i Batina, sakupljeni su tobolci domaće crne topole, te pohranjeni u plasteniku Hrvatskog šumarskog instituta. Po otvaranju tobolaca, sjeme je odvojene od kunadre pomoću sita, a zatim posijano u plastične kadice ispunjene pijeskom. Sjetva u kadicama obavljena je na dva načina, u redove i omaške. Također, dio sjemena je posijan u kontejnere od stiropora, u supstrat pijeska i treseta. Različiti načini sjetve korišteni su radi usporedbe tj. testiranja njihove učinkovitosti. Ponik je tretiran fungicidnim sredstvima. Pri pojavi prvih listova biljke su presađene u kontejnere napunjene mješavinom zemljanog supstrata i pijeska. Praćen su visinski i debljinski prirast biljaka tijekom prvog vegetacijskog perioda. Završetkom vegetacijskog perioda, selektirano je deset posto najproduktivnijih genotipova, s obzirom na priraste. U sljedećim godinama, selektirani genotipovi će se klonirati i višestruko testirati u klonskim nasadima u raznovrsnim stanišnim uvjetima. Genetičkim testiranjem i selekcijom po genotipu, očekujemo da ćemo uspjeti identificirati jedan ili više klonova koji će svojom produktivnošću biti konkurentni klonovima topole koji su trenutno u uporabi u šumarstvu Republike Hrvatske. Rezultati ovog istraživanja će osim gospodarskog značaja biti važni i za očuvanje genofonda crne topole u Republici Hrvatskoj.

Problem neredovitosti punih uroda već desetljećima remeti prirodnu obnovu sastojina hrasta lužnjaka (Quercus robur L.). Moguće je da je jedan od značajnih uzroka ovog problema prevelik broj stabala po hektaru što onemogućuje razvoj dovoljno velikih krošanja. Naime, veličina i osvijetljenost krošnje imaju značajan utjecaj na obilnost i redovitost plodonošenja. Prorede u sastojinama starije dobi nisu se pokazale dovoljno učinkovitima. S namjerom pokušaja rješavanja navedenog problema, odlučeno je započeti s istraživanjima utjecaja različitih intenziteta proreda u mladim gospodarskim sastojinama na razvoj krošanja i plodonošenje hrastovih stabala. Cilj ovih istraživanja je pronaći učinkovit „recept“ za proces konverzije mladih gospodarskih u produktivne sjemenske sastojine, čime bi se u budućnosti barem ublažio problem nedostatka žira za obnovu hrastovih sastojina. Tri pokusne plohe osnovane su na području Uprava šuma podružnica Bjelovar (2) i Sisak (1), u gospodarskim sastojinama drugog, trećeg i četvrtog dobnog razreda. Stabla su obrojčana i georeferencirana radi izrade računalnog modela ploha. Provedene su izmjere prsnih promjera, visina i horizontalnih projekcija krošanja svih stabala hrasta lužnjaka, kao i njihovo fenotipsko ocjenjivanje. Primjenom Hasenauerovog modela ovisnosti horizontalnih projekcija krošanja i prsnih promjera određene su potencijalne horizontalne projekcije stabala. Na svakoj pokusnoj plohi određena su i provedena tri intenziteta prorede: slab na jednoj, srednji na drugoj i jako na trećoj plohici, dok četvrta plohica služi kao kontrolna. Izmjere prsnih promjera preostalih stabala provedene su dvije godine nakon proreda. U radu se detaljnije obrazlaže postupak određivanja intenziteta prorede i efekt provedenih proreda na razvoj prsnih promjera i krošanja s obzirom na različite dobi pokusnih sastojina.

Na osnovanim pokusnim plohama za praćenje plodonošenja sjemena obične bukve na području Uprava šuma Podružnica (UŠP) Bjelovar, Karlovac, Ogulin i Požega, bukvica je sakupljena 2016. godine. U periodu od rujna do studenog, sjeme je sakupljano ispod pet odabranih stabala, na svakom lokalitetu, u četiri navrata. Cilj ovog istraživanja je utvrditi razinu i varijabilnost laboratorijske klijavosti sjemena. Laboratorijska klijavost sjemena je nicanje i razvoj klijanaca do faze u kojoj izgled njihove osnovne strukture pokazuje mogu li se oni u pogodnim uvjetima u tlu dalje razviti u zadovoljavajuću biljku. Kod sjemena obične bukve trajanje naklijavanja ovisi o dormantnosti i u ekstremnim slučajevima može trajati 24 tjedna. Sjeme je analizirano u Laboratoriju za ispitivanje kvalitete sjemena Hrvatskog šumarskog instituta. Metoda ispitivanja klijavosti sjemena obavljena je u sobnim klijalicama, u pijesku. Dobivene su sljedeće prosječne vrijednosti klijavosti sjemena: UŠP Bjelovar 62 %, UŠP Karlovac 62 %, UŠP Ogulin 66 % i UŠP Požega 50 %. Prosječni udio praznog sjemena je najveći na području UŠP Požega i iznosi 49 %. Ovaj je rad financirala-sufinancirala Hrvatska zaklada za znanost projektom (IP-11-2013-8131). Istraživanja i obrada podataka nastavljena su u projektu (IP-01-2018-8189).

U Hrvatskoj je selekcijom plus stabala u jednoj matičnoj populaciji pokrenuto oplemenjivanje obične smreke kao božićnoga drvca. Idući je cilj toga procesa utrđivanje optimalne procedure kloniranja izabranih plus stabala radi masovne proizvodnje reprodukcijskoga materijala (sadnica). Pretpostavka je da će se takvim načinom stvoriti kvalitetan reprodukcijski materijal koji će se odlikovati stabilnošću ciljnih fenotipskih svojstava. U radu su predstavljeni prvi rezultati istraživanja mogućnosti kloniranja plus stabala obične smreke metodom zakorjenjivanja odrvenjelih reznica. Glavni cilj istraživanja bio je utvrđivanje uspješnosti primjene raznovrsnih hormonskih tretmana na zakorjenjivanje odrvenjelih reznica starijih (10–12 godina) stabala obične smreke uzetih u ranoproljetnom i kasnojesenskom razdoblju s različitih visinskih etaža krošanja (gornja, srednja i donja trećina krošnje). Provedena su dva eksperimenta. U prvom je po 270 reznica odrezano u rano proljeće iz svake od triju visinskih etaža krošanja, na uzorku od 10 stabala. Po 10 reznica iz svake etaže tretirano je s 27 različitih tretmana (2 tipa hormona × 4 koncentracije otopine × 3 vremena trajanja tretiranja + Clonex + kontrola 1 + kontrola 2). Drugo je istraživanje provedeno na po 80 reznica odrezanih iz donje trećine krošanja od 13 izabranih plus stabala u kasnu jesen. Po 30 reznica tretirano je u trajanju od 10 sekundi sa: (i) hormonom IBA koncentracije 2500 ppm, (ii) hormonom IBA koncentracije 500 ppm. Ostatak od 20 reznica poslužio je kao kontrola. Nakon tretiranja hormonom reznice su pikirane u tzv. »paper pot saća« (sadrže 80 heksagonalnih otvora dubine 15 cm, napunjenih supstratom treset : pijesak u omjeru 3 : 1). U listopadu nakon pikiranja obavljena je determinacija uspješnosti zakorjenjivanja svake pojedine reznice, utvrđivanje broja korijenskih žila zakorijenjenih reznica te izmjere duljine najdulje razvijene korijenske žile na svakoj zakorijenjenoj reznici. Rezultati su pokazali da se stabla obične smreke u dobi od desetak godina u prosjeku mogu relativno uspješno klonirati metodom zakorjenjivanja odrvenjelih reznica uzetih iz donje trećine krošanja u kasnu jesen ili rano proljeće, i to bez ikakva tretiranja (50 %-tni uspjeh). Postotak zakorijenjenih reznica i kvaliteta novostvorenoga korijena mogu se poboljšati jeftinim, ali čini se učinkovitim tretiranjem baze reznica destiliranom vodom u trajanju od dva sata. Međutim, rezultati su pokazali da bi se tretiranjem baze odrvenjelih reznica uzetih u rano proljeće hormonskom otopinom IBA koncentracije 500 ppm u trajanju od 10 s postotak uspješnoga zakorjenjivanja mogao značajno povećati (u prosjeku do 80 %-tne zakorijenjenosti). Odrvenjele reznice uzete iz donje trećine krošanja najbolje se zakorjenjuju, čak i bez ikakvih tretiranja (50 % kontrolnih reznica, u usporedbi s 40 % kontrolnih reznica iz srednje i 20 % zakorijenjenih kontrolnih reznica iz gornje trećine krošnje). Rezultati su otkrili izrazite individualne razlike u uspjehu zakorjenjivanja reznica uzetih iz donje etaže (postotak zakorjenjivanja kretao se od 0 % do 100 %).

Međunarodni znanstveni projekt Zavoda za genetiku, oplemenjivanje šumskog drveća i sjemenarstvo Hrvatskog šumarskog instituta „Očuvanje genetskih resursa šumskog drveća u svjetlu klimatskih promjena“ financiran je novčanim sredstvima Hrvatske zaklade za znanost (IP-11-2013, 8131 ConForClim) u periodu od 2014. do 2018. godine. Osnovni cilj projekta je bio dati preporuke za očuvanje genetske raznolikosti šumskog drveća u Hrvatskoj. Projekt se provodio u sjemenskim sastojinama hrasta lužnjaka (Quercus robur L.) i obične bukve (Fagus sylvatica L.) kao modelnim vrstama u suradnji sa znanstvenim institucijama u Hrvatskoj i Njemačkoj. Genetska raznolikost i prilagodljivost obične bukve i hrasta lužnjaka ugrožena je uslijed klimatskih promjena. Rezultati ovog projekta pokazali su visoku razinu genetske raznolikosti unutar istraživanih populacija obične bukve i hrasta lužnjaka te je potvrđen ekotipski obrazac interpopulacijske genetske diferencijacije. Zdravstveno stanje u testovima provenijencija hrasta lužnjaka i obične bukve ukazalo je na statističku značajnu razliku oštećenja uzrokovanih gljivičnim bolestima i insektima. Značajan čimbenik koji utječe na pojavu i intenzitet oštećenja su lokalni klimatski uvjeti te godišnje klimatske razlike. U pokusu sušnog stresa pojedinih ekotipova pomlatka obične bukve utvrđene su razlike. Na temelju rezultata ovog istraživanja sačinjene su preporuke za reviziju uporabe i prijenosa šumskog sjemena. Rezultati projekta pružili su smjernice za podizanje kvalitete ŠRM-a u najvišu kategoriju (Zakon o ŠRM-u (NN 75/2009) i Direktiva Vijeća 1999/105 EZ). Viša kategorija jamči veću kvalitetu ŠRM-a i samim time i veću cijenu na tržištu.

Osjetljivost hrastova prema mrazu u izravnoj je vezi s njihovom lisnom fenologijom. Predviđena posljedica klimatskih promjena je povećana učestalost sušnih intervala tijekom vegetacijskih perioda. Hrast lužnjak, kao ekonomski i ekološki jedna od najvrednijih vrsta šumskog drveća, preferira vlažna staništa. Stoga je poznavanje utjecaja suše na tu vrstu od izuzetne važnosti za prilagodbu šumarskih strategija i prakse klimatskim promjenama. Jednogodišnje sadnice podrijetlom iz devet europskih provenijencija izložene su eksperimentalnoj suši tijekom dvije uzastopne godine. Evidentirane su proljetna i jesenska fenologija lista, kao i oštećenost od kasnog mraza koji je nastupio u trećoj godini. Rezultati su pokazali memorijski efekt sušnog stresa na lisnu fenologiju kod većine promatranih provenijencija, u vidu naknadnog pomaka datuma prolistavanja i odbacivanja lišća. Razlike u osjetljivosti na kasni mraz između provenijencija bile su korelirane s njihovim razlikama u fenologiji listanja. Međutim, pomak datuma prolistavanja uslijed suše uzrokovao je povećanu osjetljivost provenijencija na kasni mraz.

Sessile oak (Quercus petraea (Matt.) Liebl.) is economically one of the most important tree species in Croatia and in Rhinalend-Palatinate (Southwest Germany). The growing stock volume of sessile oak is 10 % of the total growing stock in Croatian forests and nearly 20 % in Rhineland-Palatinate. It can be found in many plant communities. Because of its broad ecological niche sessile oak is an excellent model for studying adaptation to various environmental conditions. Climate models predict the shift of forest tree species with regard to altitude and latitude. Due to rapid climatic changes, the more intense common oak decline is expected. Considering sessile oak tolerance to drought, this tree species could replace common oak on drier habitats. An international provenance trial of Croatian and Rhenish-Palatine sessile oak provenances was established in the spring of 2019 in the greenhouse of the Croatian Forest Research Institute. The acorns were harvested in the fall of 2018, and the provenances were selected with respect to the habitat and climatic conditions of the original stands and to cover the broad area of sessile oak. In April, the acorns were sown in sand and after germination they were transferred to a mixture of substrate and forest soil. During the first year, the germination, survival and height growth of young plants was observed. The first results show variability in germination and survival of provenances. Provenances originating from Rhineland-Palazinate have better germination and survival rate in comparison to Croatian provenances. The genetic variability of sessile oak in Croatia and Rhineland-Palatinate has not been studied so far and further research on this provenance trial will provide better insight into the genetic variability and adaptability of the sessile oak provenances to local habitat conditions. The results of the research will provide guidelines for the preservation of the gene pool of this important tree species.

Obična bukva (Fagus sylvatica L.) pripada među najznačajnije vrste drveća u Europi i na području Hrvatske je najrasprostranjenija. U današnjim uvjetima narušene ekološke ravnoteže teško podnosi promjene u stanišnim uvjetima koji se događaju zbog nepovoljnih biotskih i abiotskih čimbenika, te su time sposobnost plodonošenja i periodicitet uroda bukovih sastojina narušeni. Istraživanja varijabilnosti plodonošenja obične bukve provedena su u odabranim sjemenskim sastojinama na području Uprava šuma Podružnica Ogulin, Karlovac, Bjelovar i Požega u razdoblju od 2015. do 2018. godine. U tom intervalu zabilježen je izostanak i nepravilnost uroda sjemena obične bukve te bi kontinuirano praćenje uroda sjemena u narednim godinama dovelo do boljih predviđanja rezultata i preporuka za uporabu sjemena. U ovom radu prikazani su četverogodišnji rezultati istraživanja dinamike plodonošenja, te količine i kvalitete sakupljenog sjemena. Ovaj je rad financirala-sufinancirala Hrvatska zaklada za znanost projektom (8131). Istraživanja i obrada podataka nastavila su se provoditi projektom (8189).

Šume hrasta lužnjaka predstavljaju jedne od najvrednijih šuma u Hrvatskoj. Većina provedenih istraživanja o problematici plodonošenja hrasta lužnjaka kroz duži niz godina odnosi se na nepravilnost ili izostanak uroda sjemena u kontekstu otežane prirodne obnove šuma, te na procjenu proizvodnog potencijala lužnjakovih sastojina. Količine otkupljenoga žira od strane šumarija i/ili Uprava šuma Podružnica u pravilu se odnose na količine dovoljne za njihove vlastite potrebe. U godinama uroda dio sjemena ostaje u šumi, ne sakupi se. Također, sjeme se ne skuplja ako je urod slab, a kakvoća sjemena je okularno loša. Iako zbog toga ne postoje potpuni i pouzdani podaci o količini sakupljenog žira u našim šumama, postoje podaci o sakupljenim količinama žira vezano uz potrebe šumarske operative. Temeljem Zakona o šumskom reprodukcijskom materijalu Hrvatski šumarski institut je određen kao Službeno tijelo koje nadzire proizvodnju, promet i kakvoću šumskog reprodukcijskog materijala. Uzorkovanje i ispitivanje kvalitete sjemena obavlja se prema metodama koje propisuje Međunarodna udruga za ispitivanje sjemena (International Seed Testing Association (ISTA)). Cilj ispitivanja kvalitete sjemena je ustanoviti uporabnu vrijednost partije sjemena, a ispituje se na uzorcima. Svrha istraživanja je dobiti uvid u kvalitetu sjemena hrasta lužnjaka sakupljenog na području Hrvatske u vremenu od 2009. do 2018. godine. Analizirano je ukupno 2.742 uzoraka u Laboratoriju za ispitivanje sjemena Hrvatskog šumarskog instituta, te su ispitani sljedeći elementi kvalitete: sadržaj vlage, čistoća, vitalitet i masa 1000 sjemenaka. Ovaj rad je financirala- sufinancirala Hrvatska zaklada za znanost projektom (IP-01-2018-8189).

European beech is the most common tree species of forest vegetation in Croatia. In established experimental plots within seed stands of Forest administrations Ogulin, Karlovac, Bjelovar and Požega in 2016, beechnuts were collected from five selected trees in each plot. Nets for collecting the beechnuts were placed at 1 m above ground covering whole projection area of their crowns. Seeds were collected four times in the period from September to November. The goal of this study was to analyse beechnuts quality and quantity due to different seed stands. Seed analyses were performed in the Laboratory for Seed Testing of the Croatian Forest Research Institute. 1000 seed weight (TSW), moisture content and viability were assessed. All analyses were performed with regard to collection time. ISTA methods were used for testing seed quality. Statistical analyses were generated using SAS/STAT software. The results of descriptive statistics showed that the largest mean beechnut yield was in population Bjelovar (97.62 kg), while the smallest in the population Ogulin (28.42 kg). The average TSW was the highest in population Ogulin (283.6 g) and the lowest in population Požega (192.2 g). Moisture content of freshly collected beechnuts of last beechnuts collecting varied from 17 to 35 %. Viability was tested by biochemical test - the Topographical Tetrazolium Test and the best result was in population Ogulin (72%). This work has been fully supported-supported in part by Croatian Science Foundation under the project (8131).

Pedunculate oak (Quercus robur L.), which accounts for one tenth of all the forest in Croatia, is one of the most valuable forest tree species. Provenance trials, where populations of different geographical origin are tested in a common environment (common garden test), are a tool suited to allow the study of intraspecific adaptive genetic variation. The aim of the research in provenance trials is to identify provenances that are characterized by good growth and adaptability, to be used as a source of seed for future afforestation. In Croatia, two trials (Jastrebarski lugovi and Koška) were established in 2008 and 2010 for research withinspecies genetic variability of pedunculated oak populations originating from Austria and Croatia. Genetic field trials involved 22 provenances (17 Croatian and 5 Austrian) planted over a total area of 3.75 ha in 2.5 by 2.0 m spacing. Trials were established according to a randomized complete block experimental design with three replications (blocks). In total, 6 600 saplings were planted. Research of adaptive genetic variability of oak populations was conducted by analysis of height growth and survival. Survival for first analyzed year at trial Jastrebarski lugovi was extremely good (98.73%), but after it visibly decreased. The total mean height of all plants in the trial in 2016 was 441.51 cm. The mean survival of studied plants at trial Koška in first analyzed year was 84.61%. In 2016, survival was 68.3% and average height of plants was 255.79 cm.

One of the consequences of climate change in southern and south-eastern Europe is the increased frequency of dry episodes during the vegetation period. Pedunculate oak (Quercus robur L.) is both economically and ecologically important forest tree species that prefer humid habitats. Therefore, knowledge of the impact of drought on this species is of great importance for the adaptation of forestry strategy and practice to changed environmental conditions. In spring 2015, 2-year-old pedunculate oak saplings originated from nine European provenances were used for set up of a provenance trial. The trial was set up according to a split-plot RCB design. Experimental saplings were exposed to drought periods and re-watered afterwards in 2015 and again in 2016, while control saplings were regularly watered. Spring leaf phenology was scored by ordinal scale (1-7) in 2015 (before drought treatment), in 2016 (one year after drought exposure), and in 2017 (after 2 years of induced drought periods). Autumn leaf phenology was scored by ordinal scale (1-5) in 2015 and 2016. The trial was impacted by a late spring frost on April 21st and April 22nd 2017. Frost damage was scored (1 – visible frost injuries on leaves ; 0 – no visible symptoms) on all plants in the trial. Data on leaf phenology were transformed in number of days in a year when a plant reached particular phenophase. ANOVA and Tukey HSD test were used to determine statistical significance of the treatment effect on the provenances. Leaf phenology was significantly influenced by drought in majority of the provenances. Spring phenology was shifted in both years, but in opposite directions. In contrary, autumn leaf phenology was unambiguously shifted towards later senescence. Saplings exposed to drought showed significantly higher susceptibility to the late spring frost in all provenances, but one. The results indicate that differences in frost susceptibility between the provenances were dominantly caused by differences in leaf phenology (i.e. frost avoidance) and less by their active response. Absolutely the most frost-sensitive leafing phase was phenophase 7 and then phase 6 (especially in its more advanced period). Higher susceptibility to the spring frost of the experimental saplings was most probably caused by the leaf phenology shifting (earlier and more advanced leafing - higher sensitivity to the frost). Rare exceptions indicate that resistance to frost may be caused by some kind of molecular response.

Obična bukva (Fagus sylvatica L.) pripada među najznačajnije vrste drveća u Europi, a kao eurivalentna vrsta na području Hrvatske je najrasprostranjenija. U današnjim uvjetima narušene ekološke ravnoteže teško podnosi promjene u stanišnim uvjetima koji se događaju zbog nepovoljnih biotskih i abiotskih čimbenika, te su time sposobnost plodonošenja i periodicitet uroda bukovih sastojina narušeni. Istraživanja varijabilnosti plodonošenja obične bukve provedena su u odabranim sjemenskim sastojinama na području Uprava šuma Podružnica (UŠP) Ogulin, Karlovac, Bjelovar i Požega u razdoblju od 2015. do 2017. godine. Cilj istraživanja je praćenje uroda sjemena po količini i kvaliteti kako bi se utvrdio proizvodni potencijal sastojina. Zbog izostanka uroda sjemena obične bukve u 2015. godini, pokusne plohe osnovane su tijekom 2016. godine. Veličina svake pokusne plohe na pojedinom lokalitetu je 60 x 80 m, te je tijekom jeseni sakupljeno sjeme i procijenjen stupanj uroda sjemena. Praćenje uroda obavljeno je okularnom metodom te kontroliranim sakupljanjem mrežama. Okularnom metodom procijenjen je urod u 2 kategorije, ocjenama 0-2 i 0-5. U svrhu praćenja uroda bukvice kontroliranim sakupljanjem mrežama, unutar svake plohe postavljena je rasterska mreža oznaka na svakih 20 metara. Pored svake oznake odabrano je dominantno stablo obične bukve ispod kojeg su postavljena dva sjemenomjera, površine kružnog oblika, veličine 0, 5 m^2. S obzirom na projekciju krošanja, tlocrtna površina velikih mreža za sakupljanje čitavog uroda sjemena kreće se od 40 do 170 m^2, a ukupna količina sakupljenog sjemena na svim lokalitetima iznosi 245 kg. Najveća količina sakupljenog sjemena je na području UŠP Bjelovar i iznosi 98 kg, zatim na području UŠP Požega 63 kg, UŠP Karlovac 56 kg, te na području UŠP Ogulin 28 kg. Sjemenomjeri i mreže pražnjeni su četiri puta na svakoj pokusnoj plohi u razdoblju od rujna do studenoga. Sakupljen sjemenski materijal obrađivan je u Laboratoriju za ispitivanje šumskog sjemena. Obrada sjemenskog materijala sastojala se od vaganja i brojanja sakupljene bukvice, te određivanja morfometrijskih analiza. Praćenjem dinamike i količine plodonošenja u razdoblju od tri godine zabilježen je izostanak i nepravilnost uroda sjemena obične bukve. U tom intervalu bila je samo jedna rodna godina, te bi kontinuirano praćenje uroda sjemena u narednim godinama dovelo do boljih predviđanja rezultata i preporuka za uporabu sjemena. U ovom radu prikazani su rezultati istraživanja dinamike plodonošenja, količine sakupljenog sjemena te ovisnost krupnoće plodova s obzirom na stupanj uroda u 2016. godini. Ovaj rad je financirala- sufinancirala Hrvatska zaklada za znanost projektom (8131).

U radu je istraživana varijabilnost anatomske građe listova šest hrvatskih populacija hrasta lužnjaka u pokusnim nasadima Koška i Vrbanja. Cilj rada bio je utvrditi razlike u anatomskoj građi listova s obzirom na vlažnost pokusnog nasada, kao i vlažnost staništa iz kojega potječu istraživane populacije. Uzorkovani su listovi s pet jedinki iz svake od šest populacija iz oba pokusna nasada. Jedinke rasle na pokusnoj plohi Koška odlikuju se prosječno debljom donjom epidermom, debljim slojem palisadnoga parenhima, manjom masom suhe tvari lista i većom specifičnom lisnom površinom. Ovi rezultati su odraz reakcije u anatomskoj građi lista na sušne uvjete na pokusnoj plohi Koška u odnosu na nešto vlažnije uvjete na pokusnoj plohi Vrbanja. Razlike u anatomskoj građi lista između dva razlišita tipa staništa s kojega potječu istraživane populacije (greda, niza) su vrlo male, a očituju se u nešto jačoj reakciji na suše uvjete kod jedinki podrijetlom s vlažnijih staništa (niza).

Hrast lužnjak, kao jedna od triju najrasprostranjenijih vrsta drveća u Republici Hrvatskoj, ima važnu ulogu u ekonomsko- socijalnom i ekološkom smislu. Poznavanje genetske strukture tako značajne vrste šumskoga drveća temeljni je preduvjet njezina očuvanja za budućnost. Jer to, poznavanje genetske strukture, omogućuje naprednije korištenje šumskoga reprodukcijskoga materijala hrasta lužnjaka radi povećanja prilagodljivosti populacija na stresne okolišne prilike. Analiza kvantitativnih (poligenih, metričkih) fenotipskih svojstava u genetičkim testovima jedna je od metoda utvrđivanja genetske strukture vrsta šumskoga drveća. Iz šesnaest sjemenskih i jedne gospodarske sastojine koje reprezentiraju cjelokupan areal hrasta lužnjaka u Hrvatskoj, u rujnu i listopadu 2006. godine skupljen je sjemenski materijal. S dvogodišnjim potomstvom 2008. godine osnovan je genetički pokusni nasad u gospodarskoj jedinici »Jastrebarski lugovi«. Mjeren je visinski rast i određivani su preživljavanje i visinski prirast u trima uzastopnim godinama (2010, 2011. i 2012). Analiza varijance provedena je procedurom PROC MIXED u statističkom paketu SAS te su izračunate komponente varijance i statistička značajnost slučajnih efekata, tj. izvora varijabilnosti (blokovi, populacije, familije unutar populacija, interakcija blokova i populacija te interakcija blokova s familijama unutar populacija). Izračunate komponente varijance poslužile su za izračunavanje parametra QST kojim se određuje razina međupopulacijske genetske diferencijacije. Multivarijantna regresijska stabalna analiza (engl. MRT) korištena je za određivanje obrasca genetske diferencijacije populacija u nasadu, a s obzirom na okolišne (klimatske) varijable njihovih izvornih matičnih sastojina. Parametar QST bio je visok kod sva tri analizirana svojstva, što jasno upućuje na međupopulacijsku genetsku diferencijaciju hrvatskih populacija hrasta lužnjaka. Utvrđeni obrazac adaptivne genetske diferencijacije potvrđuje ekotipski obrazac, odnosno najvjerojatnije je prirodna selekcija u matičnim sastojinama (ponajprije s obzirom na vlažnost i toplinu staništa) uzrokovala genetsku izdiferenciranost lokalnih populacija.

The absence of pedunculate oak (Quercus robur L.) seed crop in Croatia have been disrupted and thus the regeneration of its forests has become increasingly questionable. Experimental plots were established on three locations in Forest administrations Bjelovar (2) and Sisak (1) in second, third and fourth age class. All plots are permanently marked, each consisting of four equal subplots of 0.25 ha, bounded on all sides by a 15 m boundary zone. Each tree is marked by a number and a georeferenced. Statistical analyses of stand and crown structures of the experimental plots were based on the data of the terrain survey at the level of the tree, the level of the subplots and the level of the plots. Criteria for selecting seed trees was determined based on the model of phenotypic selection made by defining the objective criteria for evaluating the tree form, the quality of the crown, the fullness, the spiral grain, the position in the stand and the health status of all the oak trees. In purpose to define criteria for selection of future seed trees, Hasenauers model (1977) was used. Potentially higher crown radius for selected trees were calculated according to their diameters. With analysis of potential crown growth, data about possibility of their growth in forest stands according to age were obtained. On each locality three different intensity of felling on subplots were selected: weak, middle and high. Fourth subplot was used as control. Tree marking and cutting were obtained. This paper represents the very first step in research how to create forest seed stands in young pedunculate oak forests. Therefore, in future this research want to confirm fact that selecting trees and future forest seed stands in earlier age classes can affected on growth of crown diameter and volume. Also, abundant, frequently and crop appearing in earlier age classes is expected.

We present BeechCOSTe52; a database of European beech (Fagus sylvatica) phenotypic measurements for several traits related to fitness measured in genetic trials planted across Europe. The dataset was compiled and harmonized during the COST-Action E52 (2006-2010), and subsequently cross-validated to ensure consistency of measurement data among trials and provenances. Phenotypic traits (height, diameter at breast height, basal diameter, mortality, phenology of spring bud burst and autumn-leaf discoloration) were recorded in 38 trial sites where 217 provenances covering the entire distribution of European beech were established in two consecutive series (1993/95 and 1996/98). The recorded data refer to 862,095 measurements of the same trees aged from 2 to 15 years old over multiple years. This dataset captures the considerable genetic and phenotypic intra-specific variation present in European beech and should be of interest to researchers from several disciplines including quantitative genetics, ecology, biogeography, macroecology, adaptive management of forests and bioeconomy.

Forest genetic resources conservation is necessary due to various factors that cause the loss of tree species genetic variability such as overexploatation, impact of various diseases and pests, hydrological changes as well as climate changes.Croatian Forest Research Institute according to Forest Reproductive Material (FRM) Legislative is Official body for controling of FRM production, market distribution, seed quality, and establishing of seed storage, seed and gene bank of forest trees. The main objective of the project was to create scientific foundations for the conservation of genetic diversity of two major forest tree species in Croatia. The research of the genetic variability were conducted on: i) two international pedunculate oak provenance trials (Forest Administration Našice, Forest office Koška and Forest Administration Karlovac, Forest office Jastrebarsko), ii) international common beech provenance trial (Forest Administration Zagreb, Forest office Zagreb), iii) comon beech seed stands and iv) beech greenhouse trial. The methodologies include a measurment of quantitive traits (heights and diameter growth, flushing phenology and winter leaf retention), assesment of plant disease and pest damages, monitoring of seed crops in forest seed stands, greenhouse drought stress experiment, and laboratory analyses (DNA, physiology, phytopathology and seed quality). The results and conclusions of the research are being prepared for publication in international scientific journals. Compilation of all research results will provide guidelines for conservation of oak and beech genetic resources in light of climate changes in Croatia.

Health condition of international pendunculate oak (Quercus robur L.) provenance trials in Jastrebarsko and Koška, Croatia

International beech provenance trial "Medvednica" was established 10 years ago on homonymous mountain near Zagreb, Croatia. Trial involve 21 provenance from 9 European countries which are arranged in a randomized complete block design with each provenance represented by 50 plants in three replications (blocks), planted in rectangular plots with 2.0 × 1.0 m spacing. The aim of this study was to determine the amount and pattern of adaptive genetic variability among populations for height growth, survival and flushing phenology. The data were obtained 2009 and 2016 for flushing phenology and 2010 and 2015 for height growth. Analyses of variance (ANOVA) were performed using the MIXED procedure in SAS software to determinate differentiation among provenances in flushing phenology and height. Multivariate regression tree (MRT) analysis was used to determine the pattern of genetic differentiation. Results of this study suggest genetic differences among provenances, driven by natural selection in original sites. Better insight about adaptability of the provenances in a given environmental conditions will be provided with further research in this provenance trial. Researches like this are important for identification of provenances which are characterized by good growth and adaptability, in order to use it as a seed source for future reforestations.

U Hrvatskoj je registrirano 1305 uzgajivača (tzv. dobavljača) i 358 ha nasada božićnih drvaca. U 2016. godini proizvedeno je 2 574 212 božićnih drvaca (minimalne visine 20 cm). Naši uzgajivači uglavnom nemaju genetski kvalitetan, testiran reprodukcijski materijal koji bi se odlikovao stabilnošću poželjnih fenotipskih svojstava, što, među ostalim, rezultira velikim varijacijama u kvaliteti njihova konačnoga proizvoda. Međutim, za proizvodnju ornamentalno visokovrijednih božićnih drvaca potrebno je raspolagati kvalitetnim genotipovima koji će se uzgajati u primjereno optimalnim okolišnim uvjetima. Samo podjednakom brigom za obje navedene sastavnice (genotip i okoliš) može se postići uspješna proizvodnja visokokvalitetnih drvaca. Zbog toga smo odlučili pokrenuti proces oplemenjivanja radi stvaranja i proizvodnje domaćega genetski poboljšanoga reprodukcijskoga materijala božićnih drvaca. U ovom su radu opisane faze i dinamika izvedbe započetoga oplemenjivanja naših dviju autohtonih vrsta – obične smreke i obične jele. Kao ciljna fenotipska svojstva izabrane su gustoća krošnje, oblik krošnje i debla te raspored iglica na izbojcima. Definirani su i opisani kriteriji za ocjenjivanje ciljnih fenotipskih svojstava odnosno kriteriji provedene selekcije plus stabala u dostupnim matičnim populacijama. Kandidati jedinke su izabrani u kategoriju plus jedinke ako im je ponderirana ukupna ocjena fenotipske kvalitete bila barem jednu standardnu devijaciju viša od aritmetičke sredine pripadajuće populacije. Teorijski raspon ponderiranih ocjena kretao se od 2, 0 (2, 6) do 5, 0, pri čemu je viša ocjena značila veću fenotipsku kvalitetu. Ukupno je ocijenjeno 65 kandidata stabala obične smreke. Selekcijski kriterij zadovoljilo je šest kandidata s ocjenama u rasponu od 4, 0 do 4, 5. U matičnoj populaciji obične jele ukupno je ocijenjeno 90 kandidata stabala. Od toga je selekcijski kriterij zadovoljilo 15 kandidata s ocjenama u rasponu od 4, 1 do 4, 8. Izabrane plus jedinke začetak su kolekcije biljnoga materijala koji će poslužiti za daljnje faze procesa oplemenjivanja.

The absence of crop is one of the most current problems of forestry profession because the absence of spontaneous and periodic crops in nature causes natural regeneration becoming more and more questionable. In traditional forestry, seeds are produced in forest seed stands, which are spatially defined, phenotypically higher quality and more than 80 years old. This paper represents the initial phase of a longer time cycle of multidisciplinary research why, when and how, from young regular forest stand, grows seed stand. Main goals are: 1) Selection of species and establishment of permanent experimental plots for research 2)Determine and analyse the structural elements of permanent experimental plots 3) Determine the criteria for selection of seed trees 4) Determine the criteria for the implementation of breeding and genetic meliorative procedures. Based on the scientific, professional and practical knowledge of forest management, silviculture, genetics and seed production, for the establishment of the plots, stands of pedunculated oak from second, third and fourth age class were chosen. Experimental plots are permanently marked, each consisting of four equal subplots of 0.25 ha, bounded on all sides by a 15-meter boundary zone. Each tree is marked by a number and a georeferenced. Statistical analyses of the stand structures and the structure of the crown of the experimental plots were based on the data of the terrain survey at the level of the tree, the level of the subplots and the level of the plots. Criteria for selecting seed trees was determined based on the model of phenotypic selection made by defining the objective criteria for evaluating the tree form, the quality of the crown, the fullness, the spiral grain, the position in the stand and the health status of all the oak trees. All oaks whose estimation of phenotype is greater than the minimum for one standard deviation of the total grade of the subplots phenotype, represent selected seed trees. Silviculture and genetic meliorative interventions, around selected seed trees, remove oak trees with their crowns touching or at a distance of up to 50 cm from their crowns and all other species of trees, whose height is greater than 2/3 of the height of the beginning of the crown of the selected tree.

Hrast lužnjak (Quercus robur L.) gospodarski je vrlo značajna vrsta, koja zbog svoje široke ekološke niše tvori različite tipove šuma rasprostranjene na području Europe. Cilj ovog rada bio je istražiti florističke, vegetacijske i ekološke značajke šuma hrasta lužnjaka na području Europe. U tu svrhu korišteno je 14745 fitocenoloških snimki s lužnjakom, preuzetih iz europske baze (EVA - http://euroveg.org/eva- database) i unesenih iz literature (za područja koja nisu bila sadržana u europskoj bazi). Nakon stratifikacije detaljna analiza provedena je na ukupnom broju od 3594 fitocenološke snimke. Na temelju hijerarhijske klasterske analize definirali smo pet osnovnih skupina snimki, tj. tipova lužnjakovih šuma na području Europe, koje se floristički, ekološki i geografski međusobno razlikuju. Detaljnom podjelom ih je bilo moguće razdijeliti na 17 različitih podtipova, pa su podaci promatrani i analizirani na dvije razine. Za svaku od tih pet skupina šuma, određeno je područje rasprostranjenosti, dijagnostički važne biljne vrste, provedena je DCA ordinacijska analiza flornoga sastava s pasivno projiciranim varijablama sintaksonomske pripadnosti na dijagram. Na višoj razini, između 17 različitih podtipova lušnjakovih šuma, analizirane su i uspoređene Ellenbergove indikatorske vrijednosti i provedena je korološka analiza prema fitogeografskoj pripadnosti biljnih vrsta. Dobiveni rezultati ukazuju na jasne florističke i ekološke razlike između dobivenih tipova šuma. Pri čemu su se jasno odijelile atlantske i sub- atlantske skupine snimaka od kontinentalnih, unutar kojih se izdvajaju termofilne i mezofilne šume te ekstrazonalne šume u aluvijalnim riječnim područjima.

The preserving of the genetic diversity of the forest ecosystems is the basis for sustainable management and conservation of the natural composition of the forests. Natural forests cover 95% of the total forest area in Croatia and contain different ecological types and a large number of the forest tree species. Accelerated effects of global climate change rising temperatures, falling rainfalls, and occurrence of the extreme weather, directly affect the genetic biodiversity of the species. The main objective of the project is to make recommendations for the conservation of the genetic biodiversity of the forest trees in Croatia. The research is based on the common oak and common beech as a model species. The project is financed by the Croatian Science Foundation in the period from 2014 to 2018. The results of the first year of the research (2014-2015) include activities on international provenance trials and selected seed stands of pedunculate oak (Forest administrations: Karlovac, Našice and Vinkovci) and common beech (Administration Zagreb). Monitoring (survival, height, winter leaf retention, leaf phenology, pathogens and insects) were made on provenance trials and seed stands of both species. The greenhouse experiment was established to study drought stress. The seedlings of common beech were collected from 16 different provenances throughout Croatia. Every provenance was represented with 150 plants, and a total of 2400 plants were collected. Monitoring of seed production of pendulate oak and common beach was conducted in chosen seed stands. The seed material of pendulate oak was collected in 48 collecting traps placed in the stands of different ages (middle-aged, elderly and old forests) in Forest administration vinkovci. The beechnut crops failed in 2015. For this reason, collecting traps will be set next year in chosen beech stands. All planned research activities in the first year were accomplished according to the working plan in project.

Acorns were collected in 2013 in nine Quercus robur L. populations along a latitudinal gradient from Estonia to Italy. Seedlings were raised during 2014 in a nursery and individually transplanted in 50l plastic pots with homogenised soil from a local oak forest. A greenhouse trial was established in spring 2015 according to RCBD split plot design with two main plots. Plants in the first plot did not receive any water from April 1st till July 21st (drought treatment), while plants in the second plot (control) were constantly kept at 45-50% of soil moisture content (SMC). Plants in the drought plot were rewatered on July 21st and kept at 45-50% of SMC till the end of the growing season. Heights and photosynthetic rates (PhRs) were periodically measured on all plants. The aim of the study was determining phenotypic responses of the provenances to drought and rewatering and assessing amount and pattern of among provenance genetic variation (Bogdan et al 2015ab, Sever et al 2015).Repeated measures ANOVA were performed using proc MIXED of the SAS software. Effects of 53 time, treatment, provenance and their interactions were determined. Statistical significance of differences between various effect levels was determined by Post-hoc Tukey test. Multivariate regression tree (MRT) analyses using MVpart procedure in R were conducted to reveal a pattern of genetic differentiation among the provenances (De’Ath et al 2002). MRT were done combining phenotypic data from the trial and mean annual climate data of the provenance original sites from the ClimateEU software (Wang et al 2012, Hamann et al 2011).Height growth of all provenances decreased as response to drought. Mean heights of most provenances were more than 50% lower, compared to the control on the peak of drought. However, some provenances showed milder decrease (e.g. Hungarian, Lithuanian and Estonian, whose growth decreased 35, 40 and 4%, respectively). Mean PhR of provenances in the drought treatment was also significantly lower, compared to control. For both traits, between provenance variations were highly significant (p

Pedunculate oak (Quercus robur) is a widely distributed and one of the most valuable European hardwood tree species, both economically and ecologically. We here investigated distribution patterns and niche variation of Q. robur over the large geographical scale within the species entire distribution range. To explore which environmental factors influence the species occurrence we first built an ecological niche model for Q. robur based on 239 822 occurrence points obtained from various sources and a set of 14 environmental predictors selected based on their ecological relevance, excluding highly correlated ones. Based on the resulting model, available species distribution maps from literature and species postglacial recolonization history we defined three groups of occurrence points along the northeast- southwest gradient: species distribution centre, north and south range margin. We then explored how niche occupation (realized niche) of Q. robur changes within the available environmental space characterized with the selected variables along the defined gradient. Finally, we compared niche width in the distribution centre with the northern and southern range margins. Niche width was estimated using the range of values for each of the most important environmental variables (selected based on their contribution to the model) across all points occurring in the three distribution areas. We show and discuss ecological niche differences between central and marginal stands of this still ecologically intriguing species.

Previous studies of morphological and physiological traits of pedunculate oak in Croatia have indicated genetic differentiation of populations as well as high level of intrapopulation genetic diversity. However, reported patterns of genetic differentiation vary by different authors. Research of the pattern of genetic differentiation and diversity of oak populations in Croatia was conducted by analysis of height growth and survival in a filed trial established with progeny from 17 seed stands. Analysis of variance for the studied traits revealed significant differences between populations, which confirm their genetic differentiation. Multivariate regression tree analysis (MRT) was used to determine the pattern of genetic differentiation. The populations were grouped in clusters based on climate variables of their habitats of origin and standardized arithmetic means of the studied quantitative traits in the genetic test. Populations were divided into three clusters for height trait based on beginning of frostfree period and the number of frost-free days. Populations originating from habitats where period free of spring frosts begins relatively later had lower mean heights. Populations that were highest on average originate from the habitats where early autumn frosts occur earlier on average. For the survival populations were firstly separated due to Hargreaves’s reference evaporation. This variable indicates the potential evapotranspiration of an area, and points to the aridity or humidity of a habitat. Two populations originating from relatively most humid habitats had lowest mean survival. Remaining populations were clustered based on the average temperature in winter. Populations originating from relatively arid and warmer habitats in winter performed highest mean survival. Therefore, climate in the trial during the analyzed period probably was not favorable for the populations originating from moister habitats. MRT analysis indicates ecotypic pattern of the population’s genetic differentiation driven by environmental differences in the habitats of origin. This study is part of research projects “Forest tree breeding and seed husbandry” 024- 0242108-2099 (Ministry of Science, Education and Sports of the Republic of Croatia) and “Conservation of genetic resources forest trees in the light of climate change” ConForClim 8131 (Croatian Science Foundation).

Pedunculate oak (Quercus robur L.) is one of the most valuable forest tree species in Croatia which occupy approxymately two million hectars of the country. According to previous researches, pedunculate oak trees raised from seeds usually reach its sexual maturity at age 60-70 years. To our surprise we noticed pedunculate oak trees fructifying at age of just six years in two field trials. The two trials were established in 2008 and 2010, respectively with an aim to study within-species genetic variability. Trials were established according to the randomised complete block design with three replications (blocks). Twenty open- pollinated (OP) progenis orginating from 22 provenances (17 Croatian and 5 Austrian) were planted in both trials. Each OP family was represented by five saplings per replication planted in linear plots. Each provenance was represented by 100 samplings per block planted in rectangular plots with 2, 5 x 2 m spacing. The aim of this study was to determine amount of early fructification in the trials, between- provenance differences as well as within- provenance variation for the trait.

U radu je istražen potencijal prijenosnog optičkog klorofilmetra CCM-200 (Opti-Sciences, Tyngsboro, MA, USA)u svrhu utvrđivanja stanja ishrane hrasta lužnjaka s dušikom na temelju uzorkovanja različitih tipovia lišća (lišće proljetnih i sekundarnih izbojaka). Istraživanje je provedeno na 30 biljaka uzgajanih u pokusnom nasadu tijekom dva vegetacijska razdoblja (2009. i 2010. godine). Meteorološke prilike i gnojidbeni tretman koji je bio proveden u rano proljeće 2009. godine uvjetovali su razlike između istraživanih godina s obzirom na razvoj izbojaka tijekom tercijarnoga porasta (što predstavlja potencijalni pokretač translokacije dušika u krošnjama istraživanih biljaka). Na temelju lišća proljetnih i sekundarnih izbojaka, uzorkovanoga u srpnju i rujnu 2009. i 2010. godine konstruirano je ukupno osam kalibracijskih jednadžbi. Te jednadžbe pouzdano opisuju (p < 0, 001) odnos između klorofilnoga indeksa izmjerenoga pomoću klorofilmetra i koncentracije ukupnoga dušika u lišću proljetnih i skundarnih izbojaka s obzirom na vrijeme uzorkovanja. Pomoću ANCOVA-e ispitan je utjecaj tipa uzorkovanoga lišća na homogenost parametara kalibracijskih jednadžbi (Y-odsječaka i nagiba pravaca) s obzirom na vrijeme uzorkovanja. Tip lišća nije značajno utjecao na nagibe pravaca, ali značajno je utjecao na njihove Y-odsječke u tri od ukupno četiri promatrana vremena uzorkovanja. Homogenost parametara kalibracijskih jednadžbi konstruiranih na temelju različitih tipova lišća utvrđena je samo u rujnu 2009. godine, kada je pod utjecajem produkcije tercijarnih izbojaka došlo do izjednačenja koncentracije ukupnoga dušika u oba tipa uzorkovanoga lišća. Prema tomu, jednom konstruiranu kalibracijsku jednadžbu nije moguće istovremeno koristiti za preciznu procjenu ukupne koncentracije dušika u različitim tipovima lišća. Takav rezultat dovodi u pitanje praktičnost i pouzdanost procjene stanja ishrane hrasta lužnjaka s dušikom pomoću klorofilmetra CCM-200.

International beech provenance trial Medvednica is located on the homonymous mountain near Zagreb, Croatia. Trial was established in 2007 with 21 provenances from 9 European countries. The trial was laid out according to RCBD experimental design, with each provenance represented by 50 plants in three replications (blocks), planted in rectangular plots with 2.0 × 1.0 m spacing (Ivanković et al. 2011). The aim of this study was to determine the amount and pattern of adaptive genetic variability among populations for height growth, survival and flushing phenology. Analyses of variance (ANOVA) were performed using the MIXED procedure in SAS software. Results showed significant differentiation among provenances in flushing phenology and height. Between provenance differences were further tested with post-hoc Tukey–Kramer’s test which showed higher level of differentiation for flushing phenology and lower level of differentiation for height growth. Multivariate regression tree 45 (MRT) analysis was used to determine the pattern of genetic differentiation (Hamann et al. 2011). MRT analysis of heights and survival rates separated provenances with respect to the latitude and longitude. Provenances from eastern habitats had lower mean heights and mean survival rate than those originating from the western habitats. MRT analysis of flushing phenology separated provenances with respect to the continentality variable and humidity. Provenances originating from relatively more humid habitats flushed later. With the increase of continentality and humidity, provenances showed a trend of earlier flushing. Results of this study suggest genetic differences among provenances, driven by natural selection in original sites. Further research in this provenance trial will provide better insight about adaptability of the provenances in a given environmental conditions. According to Gömöry (2009), researches like this are important for identification of provenances which are characterized by good growth and adaptability, in order to use it as a seed source for future reforestations.

Increasing drought stress driven by ongoing climate change has been identified as a major threat for the performance and persistence of Pedunculate oak (Quercus robur) forests in the southern and southeastern parts of the species’ distribution range. The potential of oak populations to cope with a rapidly changing environment has important ecological and management implications. It is assumed to depend largely on their standing genetic variation. We investigated variation at 160 SNPs located in candidate genes broadly related to abiotic stresses and bud phenology in Quercus robur populations residing near the species’ southern range margin in Croatia, to explore possible effects of local adaptation and their intrinsic capacity to cope with predicted climatic trends at the molecular level. We used complementary methods in order to test for possible natural selection effects: model-based FST outlier approaches and a landscape genomic approach testing environmental associations of SNPallele frequencies. FST-based tests revealed 8 outlier candidate SNPs showing a divergence on average 6-7 times stronger than the rest of the markers, while 37 SNPs (of which 6 outliers) showed significant environmental associations. Among them, 34 SNPs (including 3 outliers) were significantly related to one or several environmental predictors using a latent factor mixed model, while BayeScEnv detected 3 SNPs among the previous outliers that were associated with two or more environmental variables. According to identified associations, important environmental drivers of potentially adaptive population divergence are suggested to be precipitation seasonality, degree-days below 0 °C and Hargreaves reference evaporation (Eref). The overall genetic differentiation among populations being very low (overall FST ~ 0.013) and the genetic clustering being weak or not significant (depending on the method used), we discuss the biological significance of markers linked to environmental variables representative of regional-scale gradients of precipitation, temperature and aridity. Possible benefits of developing genetically informed guidelines for a climate-change integrated conservation and management of these marginal Pedunculate oak forests are also outlined.

Dosadašnja istraživanja morfoloških i fi zioloških svojstava hrasta lužnjaka u Hrvatskoj ukazala su na genetsku diferencijaciju lokalnih populacija, kao i visok stupanj genetske raznolikosti unutar svake populacije. Kako bi se dodatno istražila genetska raznolikost i diferencijacija populacija hrasta lužnjaka u Hrvatskoj, analizirani su visine i preživljenje u novoosnovanom genetičkom testu potomstva iz 16 sjemenskih sastojina i jedne gospodarske u dobi od četiri odnosno pet godina. Preživljenje u prvoj analiziranoj godini bilo je izuzetno visoko kod svih populacija, no nakon sljedećeg vegetacijskog perioda uočen je značajniji pad preživljenja. Analizom varijance za svojstvo visina za dvije uzastopne godine (2010. i 2011.), utvrđene su statistički značajne razlike između populacija. Ovisno o položaju unutar genetičkog testa za istu populaciju ili familiju utvrđeno je i različito "rasipanje" visina oko prosjeka. Proveden je Tukey-Kramer test najmanjih kvadratnih razlika za srednje visine populacija s ciljem utvrđivanja njihove povezanosti, odnosno utvrđivanja eventualnog postojanja geografskog obrasca genetske diferencijacije. Populacija HR 88 (UŠP Našice, Šumarija Koška, G.j. Lacić-Gložđe) se u obje godine diferencirala kao prosječno najviša, dok su se ostale izdvojene grupe populacija međusobno višestruko preklapale. Uspoređujući signifi kantnost razlika u prosječnim visinama između populacija s njihovim geografskim položajem nije se mogao uočiti geografski obrazac diferencijacije. Zbog utvrđenog statistički visoko značajnog efekta blokova provedena je analiza fenotipske plastičnosti istraživanih populacija s obzirom na svojstvo visine u dobi od 5 godina (PIv, RDPI), no nije utvrđen geografski obrazac razdvajanja populacija. Populacije su kategorizirane u fenotipski stabilne, nestabilne te prosječne fenotipske plastičnosti s različitim stupnjevima prilagođenosti na testne stanišne uvjete koji su vladali u analiziranim godinama. Za pomlađivanje i pošumljavanje sličnih staništa kao što je bilo stanište pokusnog nasada preporučuje se korištenje šumskog reprodukcijskog materijala iz sjemenskih sastojina, čije je potomstvo iskazalo prosječnu do visoku fenotipsku stabilnost s visokim stupnjem prilagođenosti (u smislu preživljenja i visinskog rasta). Rezultate ovog istraživanja treba shvatiti kao preliminarne i poticaj za nastavak istraživanja.

Human activities such as agriculture, traffic, industry, discharge of wastewater as well as inadequate waste disposal negatively influence the environment in which significant amounts of heavy metals have been introduced. Since plants have the ability to accumulate heavy metals from the environment with larger or smaller extent, there is possibility that vegetables we eat, due to pollution of soil where it was cultivated, contains heavy metals in concentration which exceeds prescribed limits. In this work heavy metals were analysed in common vegetable species obtained in northern- west part of Croatia, such as: red and white potato, onion, carrot, bean, lettuce and cabbage. From every species of vegetables four samples were collected. The following heavy metals were determined: arsenic (As), cadmium (Cd), chromium (Cr), copper (Cu), lead (Pb), manganese (Mn), mercury (Hg), nickel (Ni) and zinc (Zn). For determination of heavy metals atomic absorption spectrometry was used. The results have shown that from 28 collected samples, in five of them the excess of maximal allowed values of heavy metals prescribed by Ordinance on maximal allowed concentrations of particular contaminants in food (OG 146/12) was observed. From the mentioned five samples in each of them the excessive values for lead (two samples of red potato, two samples of bean and one sample of carrot) were recorded, and in one the excessive value for cadmium (a sample of red potato) was recorded. The pollution present in vegetables is probably the result of pesticide and mineral fertilizers use in agricultural production. Beside that the pollution might have the origin in disposed waste, floods, traffic and other sources of pollution located nearby.

Ljudske aktivnosti kao što su poljoprivreda, promet, industrija, neadekvatno odlaganje otpada i ispuštanje otpadnih voda negativno djeluju na okoliš u koji dospijevaju znatne količine toksičnih teških metala. Budući da biljke imaju u većoj ili manjoj mjeri sposobnost akumulacije teških metala iz okoliša, postoji mogućnost da povrće koje konzumiramo, zbog onečišćenosti tala na kojem se uzgaja, sadrži teške metale u koncentracijama koje prelaze propisima predviđene granice. U ovom radu analizirani su teški metali u čestim vrstama povrća koje je kupljeno na Varaždinskoj tržnici, a to su: crveni i bijeli krumpir, luk, mrkva, grah, salata i zelje. Od svake vrste povrća kupljena su po četiri uzorka. Određivani su sljedeći teški metali: arsen (As), bakar (Cu), cink (Zn), kadmij (Cd), krom (Cr), mangan (Mn), nikal (Ni), olovo (Pb) i živa (Hg). Za određivanje teških metala korištena je metoda atomske apsorpcijske spektrometrije. Rezultati istraživanja su pokazali da je od ukupno 28 uzoraka, u njih pet zabilježeno prekoračenje maksimalnih dopuštenih vrijednosti teških metala koje su propisane Pravilnikom o najvećim dopuštenim količinama određenih kontaminanata u hrani (NN 146/12). Od spomenutih pet uzoraka u svima su zabilježene prekoračene vrijednosti za olovo (dva uzorka crvenog krumpira, dva uzorka graha i jedan uzorak mrkve), a u jednom uzorku zabilježena je prekoračena vrijednost i za kadmij (uzorak crvenog krumpira). Uzrok prekoračenja najvećih dopuštenih količina teških metala u ispitivanom povrću je onečišćeno tlo, a mogući uzroci onečišćenja tla su: upotreba pesticida i mineralnih gnojiva u poljoprivrednoj proizvodnji, poplavne vode rijeke Drave, promet i drugi izvori onečišćenja koji se nalaze u blizini.

Genetsko modificiranje, genetsko transformiranje ili genetski inženjering je skup tehnika koje pružaju mogućnost dodavanja poželjnih osobina u superiorne genotipove biljaka, putem prijenosa gena između različitih nesrodnih vrsta, rodova, pa čak i carstava, što se inače ne događa u prirodi. S druge strane, klasičnim se oplemenjivanjem putem selekcije i križanja između jedinki koje pripadaju istoj ili srodnim vrstama također izmjenjuju i ističu određena svojstva s ciljem poboljšanja vrsta prema ljudskim mjerilima, ali je takav prijenos gena moguć i u prirodi. Sa genetskim modificiranjem na drvenastim biljkama započelo se 1987. godine na topolama (Fillatti i dr. 1987). To je prva studija u kojoj je uspješno regenerirano genetski modificirano tkivo šumske vrste drveća. Svojstva koja su najčešće predmet genetske modifikacije kod biljaka su sastav lignina, tolerancija na herbicide, otpornost na bolesti i štetnike, te kontrola cvatnje. Osim samog postupka genetskih transformacija, terenski pokusi genetski modificiranog šumskog drveća predstavljaju vrlo važan segment u cjelokupnom lancu istraživanja. Testiranje izmijenjenih svojstava u prirodnim okolišnim uvjetima pridonosi boljem shvaćanju interakcije okolišnih utjecaja i transformiranih svojstava. Iako se procjenjuje kako postoji preko 600 terenskih nasada sa genetski modificiranim drvenastim vrstama širom svijeta, u šumarstvu gotovo nema komercijalne uporabe takvih plantaža. U hrvatskom šumarstvu ne postoje naznake takvog korištenja biotehnologije. Međutim, praćenje svjetskih trendova važno je za implementaciju inozemnih iskustava u zakonsku regulativu, te za stjecanje dovoljnih količina znanja za provedbe sigurnosti i opreznosti prilikom takvih istraživanja.

In accordance with the delineation of Regions of Provenances of forests in Croatia into ecogeographic seed regions and zones, the following productive clonal seed orchards have been established: three orchards of pedunculate oak (Quercus robur L.), two of narrow-leaved ash (Fraxinus angustifolia Vahl), one of sessile oak (Quercus petraea (Matt.) Liebl, ), one of wild cherry (Prunus avium L.) and one orchard of black pine (Pinus nigra J. F. Arnold). Phenotypical selection and heterovegetative propagation of plus trees, as well as the establishment of clonal seed orchards were launched with the goal of controlling more regular yield periodicity and obtaining forest seed of good genetic quality in the categories Qualified and Tested. The orchards are regularly subjected to pomotechnical treatments, protection and other measures of maintance. Establishment and evaluation of progeny trials are provided for all clonal seed orchards. Different pomotechnical treatments (training systems) were applied to each tree species. For pedunculate and sessile oak oval spindle training system, for narrow-leaved ash spindle pyramid and for wild cherry spindle bush training system. Training systems should provide a strong framework and good light penetration in the canopy. The forming pruning is used to bring the grafts into the required training shape whereas pruning for higher yield maintains the adequate balance between the growth and the seed production. Tree pruning and training started right after the planting with a goal to gain desired canopy shape with well-deployed scaffold branches in the next 7 or 8 years. The main function of pruning is the removal of competing shoots to enforce the growth of remaining desired ones. Pruning intensity, i.e. the relation between vegetative and generative buds in the canopy determines the tree’s condition, density and yield. The balance between vegetative and generative buds can only be achieved by appropriate underground and aboveground tree parts pruning. The evaluation of genetic values of selected clones of pedunculate oak (Quercus robur L.) from seed orchards in progeny tests were also started for the purpose of obtaining increased genetic gain. Three open pollinated progeny trials have been established, representing three seed region at the age of 2 + 18 years (TP1) and at 2 + 7 years (TP2, TP3). The realised gain from the tests and expected genetic gains for height were calculated by three methods which included: realised gain (R) calculated as the difference between means of selected plus tree progenies and means of unselected control plants ; expected genetic gain by individual within provenance mass selection of first generation plus trees at the same ages as those represented in studied trial ; expected genetic gain by backward selection among first generation plus trees. In TP1 i TP3 family effect for height was statisticaly significant for the entire period, showing decreasing trend in TP1 and rising in TP3. Family effect was not significant in TP2, ponting to narrowed individual variability of plus trees in that seed region. High values of environmental variance components and family × block interactions suggest strong environmental influences in that particular trial (caused by flushing phenology), which could have led to underestimation of additive variance. High values of additive coefficients of variation in TP1 and TP3 suggest wide genetic variability of selected plus trees and good adaptability of their progeny to changing environmental conditions. In all trials the estimated expected genetic gains by backward selection among first generation plus trees after open-pollinated progeny testing showed the highest values. Realised gains were not very high during the entire period in TP1, showing the decreasing trend in recent years. In TP3 realised gain is improving, due to higher heritabilities and greater differences between selected and control families. Opposite to that, low heritabilities, non significant family variance component and small differences between selected and control families resulted in little, even negative realised gains in TP2. Genotypes from the clonal seed orchard of wild cherry (Prunus avium L.) was taken for the investigation of genetic variability and consisted of 24 selected plus trees from the area of north-western Croatia. The clones were analyzed by 15 selected microsatellite markers (SSR), chosen by the ECPGR. A wealth of allelic variations was found in SSR loci, while a high degree of polymorphism confirmed the existence not only of extensive morphological but also a very significant genetic diversity. Based on pairwise proportion of shared allele distance (DPSAM) the average genetic distance of 0.573 was calculated. The genetic distance matrix, based on pairwise proportion of shared allele distance (DPSAM), did not show a clear classification of wild cherry individuals with regard to their origin, i.e. region (Koprivnica, Bjelovar, Zagreb). The analysis of molecular variance (AMOVA) revealed a significantly higher percentage (95.88 %) of the total microsatellite diversity caused by the differences among the invidividuals within the regions, compared to that caused by the differences between the studied regions (4.12 %). The  - statistics, amounting to 0.041, was highly significant (P < 0.01) and indicates the existence of specific regional structurality of genetic diversity. Clonal seed orchards are also a nucleus of conservation of forest genetic resource using the ex situ statical method, since the relationship between the size of population and the percentage of preserved heterozygosity is thus reduced to minimal loss of total additive genetic variability. Climate changes and new habitat conditions will pose additional challenges to seed production and forest management ; in turn, this will influence their economic and social benefits, as well as biological diversity of forest ecosystems.

U radu je izvedeno idejno rješenje vodoopskrbe naselja Galižana. Uz to je napravljeno i idejno rješenje vodospreme. Rješenje se sastoji od zahvata vode, crpne stanice, glavnog dovodnog cjevovoda, vodospreme, glavnog opskrbnog cjevovoda i vodovodne mreže. Vodosprema je predviđena kao poluukopani objekt koji se sastoji od dvije vodne komore. Predviđeno rješenje zadovoljava sve relevantne propise i osigurava opskrbu vodom naselja Galižana.

Istraživanja su provedena u testu provenijencija obične bukve u kojemu je analizirano trinaest provenijencija podrijetlom iz jugoistočne Europe. Visine biljaka izmjerene su sukcesivno nakon prve tri godine rasta u nasadu, dok su fenologija listanja i zimska retencija lišća ocjenjivane skalarno u drugoj i trećoj godini. Analiza varijance provedena je s namjerom određivanja statističke značajnosti komponenata varijance uzrokovanih efektima provenijencija. REG i CORR procedure provedene su s ciljem analize povezanosti između istraživanih svojstava, kao i između svojstava provenijencija i klimatskih varijabli njihovih matičnih sastojina. Rezultati su ukazali na postojanje visokog nivoa genetske varijabilnosti za sva analizirana svojstva. Utvrđene su visoko statistički značajne razlike između provenijencija, ali su realni podaci za visine, preživljenje i zimsku retenciju lišća bili opterećeni njihovim dobnim razlikama. Korekcijom za aditivni efekt dobnih razlika izgubila se statistička značajnost diferencijacije između provenijencija za visine i preživljenje. Međupopulacijske razlike između provenijencija za analizirana svojstva testirane su Tukey-Kramer- ovim testom radi utvrđivanja eventualnog geografskog obrasca. Rezultati su pokazali geografsku strukturiranost za visine, preživljenje i zimsku retenciju lišća u smislu postepenih razlika u smjeru istok-zapad. Međutim, naoko klinalna varijabilnost bila je prvenstveno uvjetovana dobnim razlikama. Za svojstvo fenologije listanja nije utvrđena razlika između provenijencija prema geografskoj razdjelbi vrste već rezultati za ovo svojstvo ukazuju na ekotipski obrazac međupopulacijskih razlika. Utvrđena je statistički značajna povezanost prosječnih vrijednosti provenijencija s Ellenberg-ovim klimatskim kvocjentima (EQ). Provenijencije iz vlažnijih i hladnijih staništa (EQ = 12-16) su kasnije listale. S povećanjem kontinentalnosti staništa, provenijencije su pokazivale trend prosječno ranijeg listanja. Kulminacija takvog trenda bila je kod vrijednosti EQ = 26, nakon čega su provenijencije pokazale obrnuti trend tj. ponovno kasnije listanje. Za svojstva koja su bila pod utjecajem dobnih razlika nije detektirana genetska diferencijacija, ali je ista utvrđena za svojstva fenologije listanja. S obzirom na to, kao i na slična istraživanja međupopulacijskih razlika za adaptivna svojstva, veća je vjerojatnost da populacije obične bukve na području jugoistočne Europe pokazuju ekotipski obrazac genetske diferencijacije koji je oblikovan prilagođavanjem na lokalne makroklimatske uvjete. Može se preporučiti da se kod razdjelbe na sjemenske jedinice i korištenja šumskog reprodukcijskog materijala treba više orijentirati na ekološke, a ne na geografske kriterije.

Tri testa familija dobivenih slobodnim oprašivanjem plus stabala hrasta lužnjaka iz dviju sjemenskih zona (Posavine, Podravine i Podunavlja) istraživana su radi procjene genetskih parametara juvenilnoga rasta. Analizirana je varijanca i izračunati su genetski parametri i dobit od selekcije pomoću triju metoda: ostvarena dobit, očekivana dobit od individualne selekcije za prvu generaciju plus stabala unutar provenijencije kod iste dobi kao u testu, očekivana genetska dobit od povratne selekcije unutar prve generacije plus stabala. Nasljednosti za visinski rast u istraživanom razdoblju varirale su između testova od najni- žih 0, 02 do visokih 0, 98. Najniže procjene nasljednosti zbog veze s prosječnim preživljavanjem biljaka u pojedinom testu dobivene su u testu s najnižim preživljavanjem. Aditivni koeficijenti varijabilnosti (u rasponu od 12, 7 do 44, 1 %) u dvama testovima upućuju na dobar potencijal prilagodbe lužnjaka na promjene okoliša. Pokazalo se da se najveća procijenjena dobit očekuje metodom povratne selekcije u plantaži nakon testiranja selekcioniranih familija (17, 2 do 26, 3 %). U jednom su testu dobiveni niski aditivni koeficijenti varijabilnosti (6, 6 do 15, 3 %), niske procjene nasljednosti i genetske dobiti (- 0, 2 do 5, 3 %), što upućuje na smanjenu adaptabilnost istraživanih plus stabala iz pripadajuće regije. Rezultati su različiti s obzirom na sjemenske regije iz kojih potječu plus stabla. Rezultati dvaju testova pokazuju da je rast uglavnom pod snažnim genetskim utjecajem, da postoji značajna aditivna genetska varijabilnost te visok potencijal za genetsku dobit i sposobnost prilagodbe promjenama okoliša, dok rezultati u jednom testu upućuju na nisku adaptivnu varijabilnost plus stabala iz pripadajuće regije te manje mogućnosti oplemenjivanja na rast.

The aim of the study was to determine amount and pattern of genetic variation for flushing and winter leaf retention in european beech (Fagus sylvatica L.), as well as to discuss its possible causes.

Radi verifikacije važećih sjemenskih zona hrasta lužnjaka u Hrvatskoj na temelju znanstvenih spoznaja, započela su nova istraživanja genetske varijabilnosti u području prirodnog areala ove vrste. U jesen 2006. godine prikupljeno je sjeme iz tzv. priznatih sjemenskih sastojina čija je osnovna uloga izvorište kvalitetnijeg sjemena za potrebe umjetne obnove gospodarskih sastojina. U radu se prikazuju rezultati morfometrijske analize sjemena i visina jednogodišnjih sadnica podrijetlom iz 17 uzorkovanih sastojina koje reprezentiraju cjelokupni areal hrasta lužnjaka u Hrvatskoj. Iz svake je sastojine prikupljeno sjeme od 25 stabala, a na uzorku od 30 sjemenki po stablu izmjereni su duljina, maksimalna širina i masa žira, te su na temelju duljine i širine izračunati volumen žira (prema formuli za izračunavanje volumena valjka) i indeks žira (omjer duljine i širine). U rasadniku Hrvatskog šumarskog instituta osnovan je rani, rasadnički test, te su tijekom jeseni i zime 2007. godine, starosti biljaka 1+0, obavljene prve izmjere visina. Analiza varijance provedena je MIXED procedurom u SAS-u, a analizirani su: fiksni efekt važećih sjemenskih zona te slučajni učinci populacija unutar zona i stabala unutar populacija. Cilj analize varijance bio je utvrditi značajnost međuzonskih, međupopulacijskih i unutarpopulacijskih razlika za istraživana svojstva sjemena i visine jednogodišnjih sadnica. Tukey-Kramer testom u SAS-u analiziran je obrazac razlika između uzorkovanih populacija. Rezultati su pokazali da se važeće sjemenske zone nisu statistički značajno razlikovale niti za jedno analizirano svojstvo. Uzorkovane sastojine međusobno su se statistički značajno razlikovale u svim istraživanim svojstvima sjemena. Najveće prosječne dimenzije imali su žirevi iz sjemenske sastojine kasnolistajuće forme hrasta lužnjaka Domačaj-Kovačevski lug (Šumarija Karlovac), dok su najmanje dimenzije imali žirevi iz sastojine Česma (Šumarija Bjelovar). Utvrđene međupopulacijske razlike nisu odgovarale važećoj sjemenskoj razdjelbi, tj. nisu potvrdile geografski obrazac diferencijacije populacija. Utvrđena je visoko statistički značajna unutarpopulacijska varijabilnost za istraživana svojstva sjemena (razlike između stabala odnosno familija unutar populacija). Prosječne vrijednosti visine jednogodišnjih sadnica bile su najniže kod populacije Česma (Šumarija Vrbovec) i Repaš Gabajeva greda (Šumarija Repaš), dok su najviše bile kod populacije Lacići Gložđe (Šumarija Koška) i Rečićki lugovi (Šumarija Karlovac). I za svojstvo visine je uočena statstički značajna diferencijacija između populacija, iako je još veći stupanj varijabilnosti utvrđen između familija unutar svake populacije. Provedena je analiza s ciljem utvrđivanja postojanja geografskog obrasca međupopulacijske diferencijacije. Međutim niti za svojstvo visine sadnica nije se mogao uočiti geografski obrazac diferencijacije analiziranih populacija. Provedena korelacijska analiza između visina jednogodišnjih sadnica i morfometrijskih svojstava sjemena nije pokazala statistički značajnu povezanost.

Istraživanje fenologije cvjetanja klonova hrasta lužnjaka provedeno je u proljeće 2010. godine. Pokusna ploha na kojoj je istraživanje obavljeno osnovana je u proljeće 2008. godine u rasadniku Brestje (UŠP Zagreb, Šumarija Dugo Selo). Pokusna je ploha osnovana s klonovima podrijetlom iz već postojećih proizvodnih klonskih sjemenskih plantaža (KSP) hrasta lužnjaka na području uprava šuma podružnica Vinkovci, Našice i Bjelovar. Istraživanjem je utvrđena protoginija kod velike većine klonova. Od meteoroloških prilika koje negativno utječu na receptivnost ženskih cvjetova posebno se ističu veliko kolebanje dnevne temperature zraka i nagli pad relativne vlažnosti zraka. Negativan utjecaj meteoroloških prilika na trušenje polena nije utvrđen. Velika kolebanja dnevne temperature zraka, uz istodobni pad relativne vlažnosti zraka, prekida receptivnost ženskih cvjetova, što ujedno umanjuje i dužinu trajanja njihove receptivnosti. Zbog utjecaja nepovoljnih meteoroloških prilika razdoblje receptivnosti ženskih cvjetova nije bilo ujednačeno s razdobljem trušenja polena, što uvelike umanjuje mogućnost međusobnoga slučajnoga oprašivanja klonova podrijetlom iz istraživanih KSP. To se uglavnom odrazilo na našičke klonove zato što su bili vrlo ujednačeni s obzirom na početak receptivnosti ženskih cvjetova i trušenje polena, što nije bio slučaj kod vinkovačkih i bjelovarskih klonova. Klonovi podrijetlom iz KSP Vinkovci i Bjelovar imali su bolju mogučnost međusobnoga slučajnoga oprašivanja u odnosu na našičke klonove, zahvaljujući onomu dijelu klonova koji je poslije započeo s otvaranjem pupova i receptivnošću ženskih cvjetova te na taj način izbjegao utjecaj nepovoljnih meteoroloških prilika. Unatoč dobromu potencijalu međusobnoga oprašivanja našičkih klonova te sposobnosti vinkovačkih i bjelovarskih klonova da djelomično izbjegnu nepovoljan utjecaj meteoroloških prilika, ne možemo reći da su klonovi podrijetlom iz istraživanih KSP 2010. godine imali mogućnost proizvodnje sjemena koje nosi zadovoljavajuću razinu genetske raznolikosti. Stoga preporučujemo otvaranje rasprave o rekonstrukciji postojećih KSP i njihovu popunjavanju klonovima podrijetlom iz svih KSP. Tako rekonstruirane KSP ne bi bile pod tako izraženim negativnim utjecajem meteoroloških prilika, a ujedno bi zadržale dobar potencijal međusobnoga oprašivanja onoga broja klonova koji bi osigurao proizvodnju genetski kvalitetnoga sjemena.

This paper presents research results on the variability of height growth , annual growth, flushing phenology and winter leaf retention of European beech (Fagus sylvatica L.) in a provenance trial ˝Medvednica˝in Croatia. The experiment was established in spring 2007 with plants 2 and 3 years of age.