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Query: "author" (Jožica Gričar) .

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71.
Use of different growth paramaters of Norway spruce (Picea abies (L.) Karst.) to study tree response to climate
Tom Levanič, Risto Jalkanen, Jožica Gričar, M. Gagen, Primož Oven, 2006, original scientific article

Abstract: In the paper, potential analysis of various growth parameters of Norway spruceare introduced at the macro and micro levels. Dendroecological measurements give information as to xylem growth ring widths, their density and content of stable isotopes in the xylem growth rings. Needle trace method of the terminal annual shoot allows retrospective view into needle density ofthe terminal annual shoot and consequently reconstruction of the several parameters linked to the needles and air pollution. Using pinning method, it is possible to follow intra-annual dynamics of the radial growth of trees at the cellular level and furthermore investigate the effect of climatic factorson cambial activity.
Keywords: Norway spruce, multiproxy analysis, dendroecology, pinning, needle trace method
Published in DiRROS: 12.07.2017; Views: 4524; Downloads: 1832
.pdf Full text (4,90 MB)

72.
Sezonska dinamika ksilogeneze in floemogeneze pri navadni jelki (Abies alba Mill.)
Jožica Gričar, Primož Oven, Katarina Čufar, 2005, original scientific article

Abstract: Preučili smo dinamiko nastajanja ksilemskega in floemskega letnega prirastnegaplašča oz. branike pri navadni jelki (Abies alba) v rastni sezoni 2003. Vzorce floema, kambija in ksilema smo vsak teden vzeli iz dveh navideznozdravih odraslih jelk. Raziskave s svetlobnim mikroskopom so pokazale, da se je na floemski strani začela diferenciacija enega do dveh slojev floemskih derivatov še pred začetkom kambijeve aktivnosti. Kambijeva delitvena aktivnost se je začela hkrati na ksilemski in floemski strani v začetku maja. Kambijeva aktivnost se je zaključila konec avgusta. Diferenciacija terminalnih traheid kasnega lesa je potekala do konca oktobra, floemskih celic pa do konca septembra. Število celic, nastalih na ksilemski strani, je bilo večje kot na floemski. Zdi se, da je bila po obodu drevesa širina ksilemske branike bolj variabilna od floemske.
Keywords: navadna jelka, Abies alba Mill., kambij, ksilem, floem, traheide, sitaste celice, diferenciacija
Published in DiRROS: 12.07.2017; Views: 4492; Downloads: 1840
.pdf Full text (822,96 KB)

73.
Odziv kambija navadne smreke (Picea abies) na ogrevanje in hlajenje debla
Jožica Gričar, Martin Zupančič, Katarina Čufar, Primož Oven, 2004, original scientific article

Abstract: Proučili smo vpliv eksperimentalnega ogrevanja in hlajenja dela debla navadne smreke (Picea abies) na kambijevo aktivnost in celično diferenciacijo. Poskusasta potekala 30 dni; ogrevanje od 29.3.2004 do 3.5.2004, hlajenje pa od14.6.2004 do 20.7.2004. Vzorce floema, kambija in ksilema smo iz dreves odvzeli vsakih 10 dni, pripravili prečne prereze tkiv in preparate opazovali ssvetlobnim mikroskopom. Lokalno ogrevanje je po 10 dneh induciralo delitveno aktivnost kambija na floemsko stran, po 20 dneh pa tudi na ksilemsko. Po 30 dneh je pri ogrevanem vzorcu nastalo do 15 celic ranega lesa. V tem času se jeredna delitvena aktivnost kambija pri kontrolnem drevesu šele začela. Odziv kambija na hlajenje debla je bil manj izrazit. Anatomskih razlik med kontrolnim in hlajenim vzorcem po 10 in 20 dneh ni bilo. Po 30 dneh je pri hlajenem vzorcu začel nastajati kasni les, pri kontrolnem drevesu pa šele prehodni rani-kasni les. S poskusom smo demonstrirali, da je mogoče pri smrekiz umetnim ogrevanjem in hlajenjem debla vplivati na ksilo- in floemogenezo.
Keywords: navadna smreka, Picea abies, kambij, celična diferenciacija, ksilem, floem, ogrevanje, hlajenje, svetlobna mikroskopija, Norway spruce, cambium, cell differentiation, xylem, phloem, heating, cooling, light microscopy
Published in DiRROS: 12.07.2017; Views: 4776; Downloads: 2073
.pdf Full text (1,85 MB)

74.
Uporaba transmisijske elektronske mikroskopije ter uv-mikrospektrofotometrije za določanje lignina v celični steni iglavcev
Jožica Gričar, Katarina Čufar, 2004, original scientific article

Abstract: Kalijev permanganat je kot reagent v transmisijski elektronski mikroskopiji (TEM) zelo uporaben za ugotavljanje prisotnosti lignina v različnih morfoloških področjih lesa. Ker je metoda le kvalitativna, je priporočljivo rezultate, ugotovljene s TEM, potrditi še s kakšno drugo kvantitativno metodo,kot je npr. UV-mikrospektrofotometrija (UMSP). Metoda UMSP je zelo primerna za določanje vsebnosti lignina in njegove porazdelitve v lesnem tkivu. V članku je predstavljena metodologija in uporabnost TEM ter UMSP pri proučevanju porazdelitve lignina v celični steni.
Keywords: UV-mikrospektrofotometrija, transmisijska elektronska mikroskopija, kalije permanganat, svetloba mikroskopija, lignin, celična stena, les, iglavci
Published in DiRROS: 12.07.2017; Views: 4516; Downloads: 1972
.pdf Full text (823,67 KB)

75.
Differentiation of last formed tracheids in wood of silver firs (Abies alba) having various cambial productivity
Jožica Gričar, Aleš Straže, Katarina Čufar, 2003, original scientific article

Abstract: To examine the state of differentiation of the last tracheids formed in wood and the duration of cambial activity, samples of wood and cambium were taken from mature silver fir (Abies alba) trees having various cambial productivity.Semi-thin cross-sections of wood sampled in July and October, 1999, were stained with toluidine blue and observed under a light microscope. In July, three different phases of current annual xylem growth ring formation were found, as a result of various cambial tree productivity. In October, the cell divisions in the cambium were completed in all investigated trees, while the process of differentiation was not entirely completed in trees with a more productive cambium. The number of undifferentiated tracheids was higher in trees having a more productive cambium. In these trees, the cambial activity and the differentiation ended later. In declining trees, the number of cells produced by the cambium was lower and the duration of cambial activity was shorter.
Keywords: navadna jelka, Abies alba, les, traheide, kambijeva aktivnost, diferenciacija, wood, silver fir, tracheids, cambial activity, differentiation
Published in DiRROS: 12.07.2017; Views: 4551; Downloads: 2028
.pdf Full text (119,73 KB)

76.
Annual cambial rhythm in Pinus halepensis and Pinus sylvestris as indicator for climate adaptation
Peter Prislan, Jožica Gričar, Martin De Luis, Klemen Novak, Edurne Martinez Del Castillo, Uwe Schmitt, Gerald Koch, Jasna Štrus, Polona Mrak, Magda Tušek-Žnidarič, Katarina Čufar, 2016, original scientific article

Abstract: To understand better the adaptation strategies of intra-annual radial growth in Pinus halepensis and Pinus sylvestris to local environmental conditions, we examined the seasonal rhythm of cambial activity and cell differentiation at tissue and cellular levels. Two contrasting sites differing in temperature and amount of precipitation were selected for each species, one typical for their growth and the other represented border climatic conditions, where the two species coexisted. Mature P. halepensis trees from Mediterranean (Spain) and sub-Mediterranean (Slovenia) sites, and P. sylvestris from sub-Mediterranean (Slovenia) and temperate (Slovenia) sites were selected. Repeated sampling was performed throughout the year and samples were prepared for examination with light and transmission electron microscopes. We hypothesized that cambial rhythm in trees growing at the sub-Mediterranean site where the two species co-exist will be similar as at typical sites for their growth. Cambium in P. halepensis at the Mediterranean site was active throughout the year and was never truly dormant, whereas at the sub-Mediterranean site it appeared to be dormant during the winter months. In contrast, cambium in P. sylvestris was clearly dormant at both sub-Mediterranean and temperate sites, although the dormant period seemed to be significantly longer at the temperate site. Thus, the hypothesis was only partly confirmed. Different cambial and cell differentiation rhythms of the two species at the site where both species co-exist and typical sites for their growth indicate their high but different adaptation strategies in terms of adjustment of radial growth to environmental heterogeneity, crucial for long-term tree performance and survival.
Keywords: Aleppo pine, Pinus halepensis, Scots pine, Pinus sylvestris, cambium, light microscopy, Mediterranean environment, temporate environment, transmission electron microscopy, xylem
Published in DiRROS: 12.07.2017; Views: 3286; Downloads: 1485
.pdf Full text (4,63 MB)
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77.
Stanje primarne lesnopredelovalne industrije v jugovzhodni Evropi
2014, professional monograph

Published in DiRROS: 12.07.2017; Views: 2401; Downloads: 483
.pdf Full text (2,33 MB)

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