20.500.12556/DiRROS-22943 Značilnosti lesnih prirastkov v deblu in vejah oljke (Olea europaea L.) Characteristics of wood increments in stem and branches of olive trees (Olea europaea L.) Oljka (Olea europaea L.) je gospodarsko zelo pomembna vednozelena kulturna rastlina, a je zelo malo znanega o njeni strukturi lesa v različnih delih drevesa, ki je ključna za dolgoročno preživetje drevesa. V pričujočem prispevku smo primerjali značilnosti lesnih prirastkov v deblu in vejah pri oljki v Dekanih v rastni sezoni 2016. Analizirali smo tudi prevodne elemente v lesu (traheje) v posameznih tretjinah lesnih branik. Razlike v značilnostih trahej na začetku in koncu rastne sezone ter v različnih delih drevesa smo interpretirali z vidika njihove prevajalne vloge v drevesu. V ta namen smo vzorce lesa odvzeli po zaključku rastne sezone 2016, pripravili preparate prečnih prerezov in opravili histometrične analize s pomočjo svetlobnega mikroskopa in sistema za analizo slike. Ugotovili smo, da se širine lesnih prirastkov in značilnosti trahej v deblu in vejah oljk razlikujejo. Prirastki 2016 so bili v vejah približno 54 % ožji kot v deblu, površine trahej pa od 25 % (prva tretjina) do 34 % (zadnja tretjina) manjše. Površine trahej so bile primerljive v prvi in drugi tretjini branike, medtem ko je bila v zadnji tretjini površina značilno manjša, in sicer v povprečju za 17,6 % v deblu in 25,4 % v vejah. V vseh tretjinah lesnih branik v deblu in vejah smo zabeležili negativno zvezo med povprečnimi vrednostmi površine trahej in gostoto trahej. Pri oljkah se je to odražalo v primerljivih vrednostih hidravlične prevodnosti v vseh tretjinah v deblu in vejah. Ožji prevodni elementi v vejah oljk kot posledica hormonske regulacije so v skladu z univerzalno pozitivno zvezo med velikostjo trahej in oddaljenostjo od apeksa in so povezani z večjo tenzijsko napetostjo vodnih stolpcev v trahejah vej v primerjavi z deblom. Različna struktura lesa v deblu in vejah nakazuje na različno vlogo tega tkiva v različnih delih drevesa. Olive (Olea europaea L.) is an economically very important evergreen cultivated plant, but very little is known about its wood structure in the different tree parts, which is crucial for the long-term tree survival. Here, we compared the characteristics of xylem increments in the stem and branches of the olive trees in Dekani in 2016. We analyzed the conducting elements in the wood (vessels) in individual thirds of the xylem increments. For this purpose, xylem samples were taken after the end of the growing season of 2016 and histometric analyzes of the xylem tissue were performed using a light microscope and an image analysis system. The width of the xylem increments and the vessel characteristics differed in the stem and branches of the olive trees. The increments were about 54 % narrower in the branches than in the stem, and the vessel areas were between 25 % (first third) and 34 % (last third) smaller. Vessel areas were comparable in the first and second thirds of the xylem increment, while it was significantly smaller in the last third, on average by 17.6 % in the stem and 25.4 % in the branches. In all thirds of the xylem increments, we observed a negative relationship between average vessel area and vessel density. In the stem and branches of olive trees, this was reflected in comparable values of hydraulic conductivity in all xylem thirds. Narrower conducting elements in olive branches, as a result of hormonal regulation, are consistent with the universal positive relationship between vessel size and distance from the apex and are associated with higher tension of the water columns the vessels in the branches compared to the stem. The different structure of the xylem increments in the stem and branches indicates the different role of this tissue in different parts of the olive trees. les branika difuzno-porozna vrsta traheja anatomija lesa prevodnost svetlobna mikroskopija wood diffuse-porous species vessel wood anatomy conductivity light microscopy growth ring boundary true false true Slovenski jezik Angleški jezik Neznano 2025-07-10 12:31:00 2025-07-10 12:31:00 2025-10-24 03:52:48 0000-00-00 00:00:00 2025 0 0 str. 31-43 iss. 1 Vol. 66 2025 0000-00-00 Zaloznikova Objavljeno NiDoloceno 0000-00-00 0000-00-00 2025-01-01 630*81 1855-7996 10.3986/fbg0113 242108163 RAZ_Gricar_Jozica_2025.pdf RAZ_Gricar_Jozica_2025.pdf 1 AE8DB07F31FF8A33CCCDF4513DFEBFBE 5dde925288cd24ff34cbfbc9ece3ff329c03c194d7ef6eb7a41c66be23517111 4967d300-5d79-11f0-8080-001a4af901a5 https://dirros.openscience.si/Dokument.php?lang=slv&id=33435 https://ojs.sazu.si/folia_bio_geo/article/view/8073 0 41524233-5d79-11f0-8080-001a4af901a5 https://dirros.openscience.si/Dokument.php?lang=slv&id=33434 Gozdarski inštitut Slovenije Folia biologica et geologica 0 0 0