20.500.12556/RUL-68589 Seasonal ultrastructural changes in the cambial zone of beech (Fagus sylvatica) grown at two different altitudes Seasonal structural changes of cambial cells in mature beech (Fagus sylvatica L.) trees growing at elevations of 400 m a.s.l. (lowland) and 1200 m a.s.l. (mountains) are presented on the basis of light (LM) and electron microscopy (TEM). For LM, samples from trees were collected at weekly intervals and for TEM at two-month intervals from March till September, 2008. LM enabled us to follow the production of new xylem and phloem cells that lasted for 16.5 Ž 3.7 weeks at the lowland site and for 10.7 Ž 1.3 weeks in the mountains. TEM revealed differences in ultrastructure of cambial cells in the phases of dormancy, reactivation, activity and transition to dormancy. The seasonal patterns of ultrastructural changes in cambial cells were similar at both sites but their timing was different. TEM revealed changes in the fine structure of cambial cells, indicating their activation in spring and the earliest stages of cell divisions and development of new cell walls. When using LM, the onset of cambial activity could be observed one month later, compared with TEM. LM therefore enabled us to follow cambial productivity but not the activity and related cytoplasmic modifications during reactivation Fagus sylvatica kambij sezonske spremembe svetlobna mikroskopija transmisijska elektronska mikroskopija true false false Rijksherbarium/Hortus botanicus Angleški jezik Neznan jezik Delo ni kategorizirano 2015-07-10 21:08:11 2015-07-10 21:08:11 2022-07-10 03:45:07 0000-00-00 00:00:00 2011 0 0 Str. 443 - 459 no. 4 Let. 32 2011 0000-00-00 NiDoloceno NiDoloceno NiDoloceno 0000-00-00 0000-00-00 0000-00-00 630*8 0928-1541 1975177 Biotehniška fakulteta 0 0 0