20.500.12556/RUL-171425 Xylogenesis under climatic stress wood anatomical evidence of harsh conditions Nastajanje lesa in podnebni stres lesno-anatomski dokazi ostrih razmer Xylogenesis – the process of secondary xylem formation – is tightly regulated by hormonal, physiological, and environmental signals, but becomes highly vulnerable under extreme climatic stress. Drought, heatwaves, and late frosts can disrupt key stages of cambial activity, cell production, differentiation, and maturation, leading to the formation of distinct anatomical anomalies in the wood of individual tree rings. We present examples of wood anatomical features collected during xylogenesis experiments in (1) Mediterranean and semi-arid, (2) arid and semi-arid, as well as (3) cold and arctic biomes. The most typical features of Mediterranean and semi-arid biomes – L-type IADFs showing xylogenetic plasticity – are shown in Pinus pinea, Arbutus unedo and Quercus ilex. Drought-induced disruptions of xylogenesis in arid and semi-arid biomes are illustrated by E-IADFs in Arbutus unedo and dark rings in Pinus halepensis. Finally, frost rings in Rhododendron myrtifolium and blue rings in Pinus sylvestris are presented as typical wood anatomy anomalies that occur due to disrupted cambial production and cell differentiation at the beginning or the end of vegetation period in the harsh conditions of cold arctic biomes. Ksilogenezo - proces nastajanja sekundarnega ksilema (lesa) - uravnavajo hormonski, fiziološki in okoljski signali, vendar proces lahko zmotijo ekstremni podnebni dogodki. Suša, vročinski valovi in (pozne) zmrzali lahko prekinejo ključne faze kambijeve aktivnosti, celične produkcije, diferenciacije in nastanka zrelih celic, kar vodi v nastanek izrazitih anatomskih anomalij v lesu posameznih branik. Predstavljamo primere anatomskih sprememb lesa, zbranih med našimi raziskavami nastajanja lesa v (1) sredozemskih in polsušnih, (2) sušnih in polsušnih ter (3) hladnih in arktičnih biomih. Najbolj značilne lastnosti sredozemskih in polsušnih biomov, so znotraj-letne variacije gostote IADF tipa L. Te kažejo ksilogenetsko plastičnost in so prikazane pri vrstah Pinus pinea, Arbutus unedo in Quercus ilex. Motnje ksilogeneze v sušnih in polsušnih biomih, ki jih povzroča suša, ponazarjajo IADFi tipa E, ki smo jih zaznali pri vrsti Arbutus unedo in temne branike pri vrsti Pinus halepensis. Nazadnje so predstavljene mrazne branike pri vrsti Rhododendron myrtifolium in modre branike pri Pinus sylvestris, kjer je bila zaradi zmrzali motena kambijeva produkcija in/ali diferenciacija celic na začetku ali na koncu vegetacijske dobe v ostrih razmerah hladnih arktičnih biomov. xylogenesis = wood formation wood anomalies in tree rings intra-annual density fluctuation (IADF) dark ring frost ring blue ring ksilogeneza = nastajanje lesa les anomalije v branikah znotraj-letna variacija gostote = IADF temna branika mrazna branika modra branika true false true Angleški jezik Slovenski jezik Članek v reviji 2025-08-26 08:46:11 2025-08-26 08:46:15 2025-09-01 03:55:06 0000-00-00 00:00:00 2025 0 0 Str. 65-76 št. 1 Let. 74 2025 0000-00-00 Zaloznikova Objavljeno NiDoloceno 0000-00-00 0000-00-00 2025-01-01 630*811.2 2590-9932 10.26614/les-wood.2025.v74n01a05 246582275 RAZ_Balzano_Angela_2025.pdf RAZ_Balzano_Angela_2025.pdf 1 B5761E76A080B6C2450EE7C56159C5BD 7a9c18a1334a08c08f76c3d72f2f5d28a957fa2466ec2eeceb24c6454f14c647 7dfff02d-8248-11f0-9328-0050569b8976 https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=214741 https://journals.uni-lj.si/les-wood/article/view/22768 1 3f18a470-8248-11f0-9328-0050569b8976 https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=214739 Biotehniška fakulteta Les 0 0 0