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Vliv věku jedince na xylogenezi smrku ztepilého (Picea abies (L.) Karst.) během vegetačního období
Čechová, Marie
In this work, it was analyzed whether the age of the tree has an influence on the radial growth in stem. Samples were taken from trees of different ages during the growing season at Rájec-Němčice research site in 2017. Paraffin blocks were made from the samples to cut the micro-incisions and then permanent microscopic preparations were made. Cambium and xylem cells produced last year were observed using a microscope. Cambial activity was 21 days longer in young trees. Maximum cell production was at the end of June. The average total increment was 49 cells in young trees and 38 cells in old trees.
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Xylogeneze buku lesního (Fagus sylvatica L.) na Drahanské vrchovině v průběhu dvou po sobě jdoucích vegetačních období
Sýkora, Štěpán
Štěpán Sýkora xylogenetics off European beech (Fagus sylvatica L.) on location Drahanská vrchovina. Bachelor thesis deal with cambial acitvity and the proces of cell differentiation of beech during two consecutive growing seasons according to weather conditions. On the research area Rájec Němčice in 2014 there was carried out on three sample trees. Sampling took place over a weekly period from 13.3. to 20.11. 2014. From taken samples were developed sustained microscopic preparations, from wich the data were obtained by using a light microscope. Monitored were the beginning, the maximum of produciton and the decrease of cambial aktivity. On the new cells there was observed the proces of the cell diferentiation from phase of radial expansion to ending of growth ring production. The obtained data were interleaved by applying the Gompertz function and the individual maximum radial additions and the period of creation of the growth ring and its parts were determined. Formula clause:nnn
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Analýza tvorby dřeva buku lesního (Fagus sylvatica L.) na buněčné úrovni
Mikel, Jakub
The bachelor thesis describes the analysis of the wood creation of the europen beech wood (Fagus sylvatica L.) at the cellular level. The samples of three young trees were taken at weekly intervals, for two consecutive vegatation periods in 2013 and 2014. Subscriptions took place between 2013 and 2014, using the trephor. Permanent microscopic preparations were made from mikrocores and were observed using a light microscpe. This work explores the cambial aktivity and the proces of wood formation during the year season (from March to April). By using the light microscope, the beginning of cambial activity, its maximum activity and termination was recorded. Furthemore, the course of the cell differentiation in individual phases (radial expansion, the sekundary wall formation and lignification) were observed. Measured values of radial expansion were interleaved by the curve of the Gompertz function, which set the optimal model of radial increase during the year season. The date of maximum daily gain and average increase per day was determined from obtained data. Observing the cambial aktivity and the cell diferentiation in relation to climatic conditions will help us to understand the link between the wood formation and the influenc of the environment. The obtained results were compared with the professional literature.Formula clause:yes
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Analýza procesů xylogeneze a floemogeneze u jedinců smrku ztepilého (Picea abies (L.) Karst.) ve dvou vegetačních obdobích
Kašpar, Miroslav
KAŠPAR M.: Analysis of xylogenis and floemogenesis of Norway Spruce (Picea abies (L.) Karst.) during two growing seasons. The thesis deals is focused on finding and evaluating the creation of wood and phloem of Norway spruce during the vegetation period 2015 and 2016 at the reasearch area Rájec-Němčice. Six representative trees were selected on the surface and samples were taken periodically. Permanent microscopic slides were prepared and examined for the samples obtained. The activity of cambium, the different phases of differentiation of wood and bast elements and the rate of growth using Gompertz function were evaluated. The data collected for each year were compared with each other and compared with the results of other authors. Growth variations were noted within two growing seasons. Statistically significant differences were seen in the number of kambia cells, whether in dormancy or during the active period. There were statistically significant differences at the time of termination of the individual cell phases. The different values of the years also resulted from the results of the Gompertz function. Generally speaking, in 2016 the growth dynamics was more intense and the number of cells generated was higher than in the previous year.
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Monitoring tvorby dřeva a lýka buku lesního (Fagus sylvatica L.) na buněčné úrovni na výzkumné ploše Rájec - Holíkov
Veteška, Ondřej
Monitoring of cambial activity in sample trees during growing season 2013 and 2014 was the aim of this thesis. This study summarizes the findings about the variations in the cambial zone, the radial increment of stems, the differentiation process of xylem and phloem formation. The changes in cambial zone observed at the cellular level were made possible by the periodical sampling. Periodical samples - microcores were taken with the Trephor tool at weekly intervals from March to November. The permanent microscope slides were made of microcores. The number of the permanent microscope slides provided information about the actual cambial activity at the time of sampling. Variations and results of the cambial activity were evaluated in relation to the climatic conditions of the research site. The unfavorable climatic conditions were noted in the growth response of sample trees, especially in 2014. The radial xylem increment was 1012±489 µm in 2014. The maximum daily increment of xylem 13±4 µm was recorded between 29 May and 26 June 2014. The total tree ring width was 1655±444 µm in 2013. The maximum daily increment of xylem 27±13 µm was recorded between 13 June and 11 July 2013. The xylem formation lasted for 91 days in 2013. The xylem formation was 9 days shorter in 2014.
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Analýza tvorby dřeva buku lesního na výzkumné ploše Rájec-Holíkov
Porvalík, Radim
This bachelor thesis presents xylem formation of common beech (Fagus sylvatica L.) on sample plot in Rájec-Holíkov in one year period,specifically exeptionally dry year 2015. Total of 6 trees were used as sample trees of which micro bores were obtained around the grith with the Trephor apparathus in chronological order from 23rd March to 12th November, once in a week. In laboratory, the samples were processed into permanent slides and analysed with a light microscope. The processes of xylem growth and xylem maturing from the initial phase to the complete differentiation were observed. First symthomps of initial phase and cambium activity occurred when mean day temperature reached 7,5 °C corresponding to end of April and start of the May. The secondary cell wall and gradual lignification occurred from 4th June 2015 (155 DOY) to 20th August 2015 (232 DOY). Fully lignified cells were occurring gradually until October. Total growth of tree ring lasted 90 days. The mean size of newly formed tree ring size 1235 µm according to Gompertz function.
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Vliv částečného poškození kůry na anatomickou stavbu nově vytvořeného dřeva u juvenilních jedinců borovice lesní
Pýcha, Tomáš
The aim of this thesis was to determine whether bark damage on one side of a stem causes changes in wood anatomy. During the growth season a strip of bark was removed on half the circumference of stem of eight trees. After the end of growth season thin cross sections of stems were made from above and below the removed strip of bark. On these sections number of tracheids, their dimensions and radial wood increment were measured. Number of tracheids and radial wood increment on damaged side of the stem was 30-50 % lower below than above the wound. Radial width of tracheids on the damaged side of the stem was 14-16 % lower than on the undamaged side. Tracheid cell wall thickness was also lower on the damaged side of the stem where it was 7-20 % thinner compared to the undamaged side.
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Analýza tvorby buněk sekundárního xylému a floému borovice lesní (Pinus sylvestris L.) v reakci na stres suchem
Fajstavr, Marek
Scots pine (Pinus sylvestris L.) is a long-term economically preferred woody species not only from the standpoint of its wood production but also thanks to its tolerance to extreme climatic factors, environmental modesty, and resistance to drought stress. In recent years, however, due to the action of the changing climatic conditions, this economically significant woody species withers. Its increment in the natural ecotype is affected by the adaptability to the increasing intensity of temperature extremes (prolonged heat waves). The combination of the lack of precipitation and extremely high air temperatures (even in the spring season) will significantly affect the resistance of this woody species to drought stress. This thesis is focused on the analysis of the secondary xylem and phloem cells formation of Scots pine depending on the physiological and morphological changes due to the affecting drought stress. Within the scope of the forming radial cells in individual growing seasons (2013–2016), it has been evaluated how the synergy of the specific factors affecting the overall anatomic structure of the annual ring and the vitality of the examined woody species was expressed in the formation, differentiation, and overall structure of the cells. During the four growing seasons (2013–2016), micro-cores (diameter 1.8 mm) were taken in weekly intervals in the research area in Sobesice of xylem and phloem (including the cambial zone) using the Trephor increment borer. From these micro-cores, permanent microscopic slides of the cross-section were made, on which the analysis of the cambial activity, cell formation, cell differentiation with time, and the evaluation of the morphometric parameters of the formed of xylem and phloem cells were performed. It was found that in each monitored growing season, the drought stress has shown, which was reflected by the dropped of the soil water potential (below -1 MPa) and the intensity of transpiration, which led to the stress reaction of the cambium. The reaction of the drought-stressed cambial zone has been expressed by the decreased activity (a sudden drop of the number of dividing cells) and subsequently, during the recurrence of precipitation, by the reactivation when an increase of the number of dividing cells was observed again. This factor initiated the formation of the intra-annual density fluctuations (IADF), i.e. the formation of the so-called false annual ring. The sensitive reaction of the cambium to the drought stress affected the cell production time, the number of formed cells, and also the time of differentiation of individual tracheids, which was expressed by the reduction of the radial dimensions and cell wall thickness of the tracheids. The artificially induced stress by stem girdling intensified the concurrent drought factor and in the area below the girdling, the cambial activity has stopped within two weeks after the performed treatment. The formed cells were not fully differentiated, so the zone of typically thick-walled cells of latewood was missing in the annual ring. The following growing season, the radial increment was only formed in the area above the girdling (without the latewood zone) and in the second half of the growing season, the trees gradually died. The activity of the plant hormone IAA was also affected by the drought in the summer season, when its concentration dropped below the measurability threshold (2 µg sample-1). At the time of the IAA concentration drop, latewood tracheids began to form and the phloem cell formation was completed. The synthesis and activity of the soluble low-molecular carbohydrates correlated with the course of the cambial activity and the cell differentiation phases, where the dynamics of the concentration also matched the timing of the formation of the individual cell formation phases. With phloem cells, a significant variability in the morphological dimensions has not been observed compared to xylem cells. The phenology of the needles indicated the cell wall formation phases and the initiation of the latewood tracheids. Due to the fact that the needles were fully formed in the season of the spring tracheids formation, their phenology did not reflect the drought stress which was recorded mainly in the summer season. Also, the increment of phloem was formed in the spring season. It has been presented for a long time that coniferous woody species react to the drought stress by thicker cell walls formation of the latewood tracheids. However, it has been observed within the scope of the research of this thesis that the water deficit affected the cambial activity, which has expressed itself on the intensity of the cell formation and the time of their differentiation. Due to this process, tracheids with smaller radial dimensions and a narrower cell wall were formed. This gradually causes structural changes of the formed annual ring, where the typically earlywood and latewood tracheids (classified according to radial dimensions and thicknesses of cell walls) may form independently on the growth seasonality. Especially in cases of IADF formation or in combination with the case where latewood is not even formed, a problem with the validity of the classification according to the so-called Mork’s criterion begins to occur. The understanding of the effect of the specific metabolic and physiological changes on xylem and phloem formation of Scots pine helps to clarify the issues of forestation and overall wood production of this economically significant woody species.
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Analýza tvorby xylému ve dvou porostech odlišného věku u jedinců smrku ztepilého (Picea abies (L.) Karst)
Rolincová, Petra
Analysis of xylem formation in the stands of different ages was realized in research area in Drahany Highlands. The main objective was to compare the growth dynamics between young and old trees during the growing season 2014. Samples were taken at weekly intervals by means of Trephor tool. For these samples were made the micro-incisions with using the method impregnation microcores paraffin and slicing on rotary microtome. The results were compared with studies with the same focus. Cambial activity of old trees was 20 days shorter than in case of young trees and the number of cambial cells of old trees was smaller than young trees. Trend of xylem cell development was the same for both age groups, but in old trees the beginning of differentiation was shifted by 11-14 days later. Production rate of cells was higher in young trees. Total number of cells of newly formed annual ring was in young trees 42 % higher.
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