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Vitality and germination juniper (\kur{Juniperus communis}) seeds
OKROUHLÁ, Ilona
The thesis focuses on the fertility and vitality of common juniper seeds (Juniperus communis). Random galbula samples from two areas were tested. Amount of seeds per one galbula were compared, seed fullness and vitality were compared via the colouring method, as well as the weight, as well as a try to cancel the dormancy using gibberelinic acid GA,, following the aim to plant more seedlings. The results were compared to seed values and to findings from other authors. If the issue of lower seed fullness and vitality is clarified, more suitable methods of juniper population proliferation and support maybe worked out.
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Seed germination and seedling recruitment of Iris sibirica depending on the type of management
HOŘEJŠÍ, Edita
This work continue on a bachelor's work which investigated production characteristics of the plant species Siberian Iris (Iris sibirica). The aims of the presented work are reproductive properties by seeds of Siberian Iris in relation to the seed germination and with various meadow managements. Seeds of Siberian Iris (collected in 2015 and 2016) were investigated in laboratory condition and at meadow near the pond Dolní Stržený (Dlouhá Lhota, of the Tábor District). Seeds were divided into groups according to 4 treatments: without intervention, scarification, thermal stratification and cold stratification. The field experiment runs from September 2016 to August 2017.The aim was to find out the most appropriate type of management (mowing, disturbance) that would promote seed germination and seedling recruitment. Results from the both experiments: a positive effect of germination after the scarification, better recruitment of seeds in square without intervention, seeds probably needs to be stored for a longer period before sowing. These results cannot be generalized, because small number of repetitions were performed. All the obtained data was discussed and recommendations for the plant management were formulated.
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Interakcia fytohormónov a vonkajšich faktorov v dormacii hľúz ľuľka zemiakového (Solanum tuberosum L.) odvodených v explantátovej kultúre
Maco, Roman
Microtubers were obtained from potato plants (Solanum tuberosum L.) cultured in vitro, they were used in following experiments. The impact of growth regulators (FLD, AgNO3, BA, ABA) was monitored in length of dormancy. The content of ABA in the budding tubers and the content of endogenous CK (BA, IP, DHZ, DHZR, Z) was determined during the dormancy as well. Production of ACC, ethylene, O2, CO2 and ethane was determined by gas chromatography. Variants containing FLD, AgNO3 and BA had a significant impact in the shortening of dormancy and stimulation the growth of buds microtubers. When they were used the occurrence of budding tubers was increased by 30-40 % over the control. Variant of ABA inhibited the growth of buds. ABA content correlated with the process of dormancy and the occurrence of budding tubers. The highest content of ABA was in variant with freshly collected dormant tubers. Concentration of various CK was dependent on the type of CK and monitored variant. Generally, It was slightly increased with occurrence of budding tubers.
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Ecophysiological relevance of extreme sensitivity of orchids to nitrates
Figura, Tomáš ; Ponert, Jan (advisor) ; Tylová, Edita (referee)
Many orchid species are seriously endangered at present. Reasons for their disappearing from natural habitats remain often unclear. Orchids depend on mycorrhizal symbiosis in nature, however only little is known about this symbiosis. Seeds of some species do not germinate in vitro, making their cultivation for scientific and rescue purposes impossible. We found that seed germination of one of such reluctant species, Pseudorchis albida, is strongly inhibited by nitrates even at extremely low concentrations. As this species prefers oligotrophic mountain meadows, nitrate-induced inhibition probably take place in natural conditions. Surprisingly, we found similar but slightly weaker inhibitory effect also in typical mesophillic species and even in slightly eutrophic ones. The sensitivity to nitrates correlates with trophy level of species canopy. This inhibitory effect of nitrates could be weakened by application of a range of growth regulators, including auxins, cytokinins and gibberellins, and also by mycorrhizal fungi. The action of nitratereductase is essential for this inhibitory effect of nitrates. Experiments with NO donors, scavengers, and NO quantification are pointing right at NO as compound which perhaps mediates nitrate inhibitory effect. Based on these results, the nitrate inhibitory...
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Analysis of biological features of Capsella bursa-pastoris (L.) Med.
Schneebergerová, Tereza ; Hamouz, Pavel (advisor) ; Holec, Josef (referee)
The aim of this bachelor thesis is to determinate selected biological characteristics of shepherd´s-purse, which have impact on the establishment and expansion of its populations in field crops. In particular, development of primary dormancy was studied and the effect of factors that influence the dormancy and germination of seeds was determined.
Shepard´s purse is an annual or biennial herb of the cabbage family, which is classified as winter annual weeds. Primarily infest the winter and spring crops, rapeseeds, potatoes or forages. It appears from lowland to foothills, so biological features of individual population can be very different. The ways of control are shallow tillage or herbicidal treatment.
After harvesting of ripe seed the first experiment was set to define the primary dormancy. Remaining seeds were stored in two different types of environment. Part of seeds was stored in the dry at 20 °C. Others seeds were stratified at 5 °C. Effect of storage conditions on primary dormancy was tested every two weeks. Seeds were germinated for
1 week in grow chamber under the influence of various factors such as different light mode, type of water and type of media for germination.
The results were processed by multiple-factor analysis of variance. Fresh seeds showed a strong primary dormancy at constant temperatures of 10 °C and 20 °C. Treatment with fluctuating temperature (20/10 °C), filter paper, drinking water and stored in dark had the highest germination rate (10.75 %). Seeds stratified at 5 °C had increase in germination in first weeks, but lost it during storage. On the other hand, seeds stored in dry at 20 °C firstly were in dormancy, but they lost it gradually during storage.
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Biology, seed characteristics and growth establishment of comfrey (\kur{Symphytum officinale }L.)
KOVÁŘOVÁ, Jaroslava
The thesis titled "Biology, seed characteristics and growth establishment of common comfrey (Symphytum officinale L.)" dealt with the evaluation methods of reproduction comfrey and evaluation of the impact of environmental conditions to the grow of comfrey. Further it dealt with germination tests and their statistical evaluation while respecting the specific work with seeds. They were evaluated seed characteristics, which are reflected in the growth of these plants arising both in soil and in a laboratory environment. Literary part gave information about biology, characteristics, morphology, prevention and regulation of comfrey even more its cultivation, nutrition of the grassland and seed characteristics, germination and dormancy. In the final section of work was monitored coverage, botanical images, representation of herbaceous species growing near comfrey. The study also discussed vernalization, size of comfrey leaves, growth and development depending on the content of nutrients (soil fertility) and water in the soil and on the number of cuts to its growth. There were designed a suitable ways of reproduction and growing of comfrey.
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Charakteristika biologických znaků, průběhu dormance a fenologie u vybrané skupiny broskvoní
Sýkora, Jaroslav
The aim of the diploma thesis was to find out the termination date of endogenous dormancy of bud flowers within the selected set of apricot varieties and simultaneously keep track of the development of various phases of microsporogenenesis. The last goal was to capture the phenological indicators of flowering and fruit development. The experimental part describes material and methodology tested on the peach varieties at Horticultural Faculty in Lednice in a two-year experiment during 2013-2014. The temperature curve was significantly different in both years. Year 2013 was characterized by gradual and lengthty progression of low temperatures, and by late termination of endogenous dormancy. Year 2014 was entirely unlike the previous one in its rapid progression of above-average temperatures and dynamic emersion of varieties from dormancy. After evaluating the results the varieties were divided into three groups with short, medium and long period preceding the termination of dormancy. The results of the observation of microsporogenesis phases shows that development of each phase is not uniform in all varieties of monitored peaches. The pollen grains development rate is greatly influenced by the temperature curve. Varieties with late termination of dormancy and slow development of microsporogenesis phases are less susceptible to impairment of the flower buds by late spring frosts.
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The evaluation of seed properties of Lathyrus pratensis and Vicia cracca and their employment in permanent grasslands.
KRATOCHVÍLOVÁ, Eva
The theme of the thesis are climbing legumes meadow vetchling (Lathyrus pratensis) and tufted vetch (Vicia cracca). The literature search defines watched kinds of legumes and their occurence in permanent grassland. There is summarized seed growing of legumes because of its problematic production. Legumes are valuable components of grassland especially thanks to fixation of nitrogen and high capacity of proteins. The practical part is focused on observation of floristic compilation of watched locations for three years. Particular locations were compared from the point of view of changes in land management and weather. Pods and seeds of observed kinds were collected and evaluated in single years. Experiments of seed's field germination were done after different period from picking and in case of various treatment.
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Regulácia dormancie hľúz ľuľku zemiaku (Solanum tuberosum L) odvodených v in vitro podmienkach
Maco, Roman
Potato tubers were induced on MS medium with reduced nitrogen content. It was monitored dormancy length, size and weight of tubers and the impact of reduced nitrogen to the tubers as well. Thesis also studied the impact of various substances (FLD, AgNO3, ABA, CEPA, sorbent ethylene) on dormancy. It was stated production of ethane, ethylene and CO2 by gas chromatography. The oxygen content was determined by an oxygen detector. Substances FLD, AgNO3 and sorbent ethylene had stimulatory effects on sprouting and also the reduction of dormancy. ABA and CEPA caused inhibition of sprouting and extension of dormancy. All substances thus increased oxygen consumption and CO2 production. The concentration of ethane was at low values under the control at all applied materials. It pointed out that there was no damage to the meshes. Effect of reduced nitrogen was not very significant and actually differed in only one variant.
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