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Využití detekce specifických alel genů VRN a PPD pro hodnocení ranosti ječmene
Kárníková, Barbora
This bachelor thesis focuses on the issue of the relation between the presence of specific alleles of genes PPD-H1 and VRN-H1 and the earliness of barley. The evaluation was carried out in a set of recombinant inbred lines (RIL) resulting from reciprocal cross of the semi-late spring barley variety Malz with the spring variety Tadmor, which has a short vernalization requirement and has an early to very early character under certain conditions. First part of the work done was an execution of a field trial and continuous monitoring of its state in rela-tion to phenological development, habitus type and health. The second part consisted of an in-laboratory analysis of the presence of alleles related to vernalization and photoperiodism. The occurrence of PPD-H1 and VRN-H1 alleles, which influence the nature of response to photoperiod requirement fulfilment and also the fulfilment of vernalization requirement, was studied within a set of chosen contrasting lines of generation F10. Relation of these alleles to habitus type, thousand kernel weight (TKW) and the content of nitrogen derived substances was also analysed. The results indicate that within the given genetic background, presence of the dominant allele of the PPD-H1 gene which is passed onto the lines by the Tadmor parental variety, had the most impact on earliness. Within the set of 26 chosen evaluated lines, only one did not exhibit the expected earliness typical for the type of PPD-H1 allele that was present in it’s genome. A statistically conclusive relationship between earliness, habitus type and thousand kernel weight (TKW) was revealed in the results of the evaluation of the relation of earliness to specified morphological and quality-related kernel traits. Relation between earliness and the content of nitrogen derived substances was not statistically conclusive.
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Effect of light on microalgae growth
Adamec, Matěj ; Sukačová, Kateřina (referee) ; Naď, Martin (advisor)
Light is one of the key elements affecting the growth of photoautotrophic algae in photobioreactors. For optimal cultivation in such a device, sufficient access to light radiation to the microalgae is required sufficient light intensity is needed. In this work, considerable attention is paid to the influence of light during the whole photosynthesis process. Viable solutions for the illumination of the photobioreactor by natural and artificial light are evaluated in detail, including a description of its main parameters. The design of a programmable illumination for a newly designed photobioreactor with eight horizontal tubes and a control calculation of PPFD (Photosynthetic Photon Flux Density) were performed. Afterwards, the designed illumination was implemented on the newly built photobioreactor to evaluate the effect of photoperiod length and LED light coloration on the actual microalgae cultivation. Based on these data, the optimal photoperiod length could be determined, and ratios of 12:12, 18:6, and 24:0 (light phase:dark phase) were tested. Finally, to evaluate the spatial distribution of the photobioreactor illumination, CFD simulations of selected photobioreactor tubes were performed using simulation software ANSYS FLUENT.
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Faktory ovplyvňujúce nástup pohlavnej dospelosti u rýb a možnosti skrátenia generačného intervalu - prehľadová štúdia
GARAYOVÁ, Margaréta
The aim of the this thesis was to develop a comprehensive overview study on the onset of sexual maturity, the factors that affect the onset and the possibilities of shortening of generation interval. Sexual maturity can be understood as a trait, resp. phenotypic expression, with individuals undergoing puberty before reaching adulthood. Puberty in fish is very important for farmers or breeders, as it affects a number of important parameters. The onset of puberty is influenced by many factors, either internal or external. Internal factors include fish species, genetic predisposition, health and fitness condition, the size and age of fish, sex of fish, and most importantly, the endocrine system. Based on the role of sex, we can state that in most species of fish in the Czech Republic and Slovakia, females mature later than males. The fact that individuals are sexually mature points out the functionality of the brain-pituitary-gonadal axis, which role is indispensable. GnRHs (gonadortropin-releasing hormones) or otherwise so-called hormone triggers with their effect on the pituitary gland and the secretion of LH (luteinizing hormone) and FSH (follicle-stimulating hormone), which further affect the gonads, are the center of this axis. Another gland with internal secretion that influences the onset of puberty is the pineal gland with the hormone melatonin. There are many external factors, but the thesis focuses on factors influencing the onset of sexual maturity of our fish and these are water temperature and photoperiod. From the obtained information, we can claim that in carp fish the key factor is the temperature, whereas in salmonid fish it is the photoperiod. For perch fish, this is still not clear. Taking into consideration carp fish, we can shorten the generation interval with a constant higher temperature. On the other hand, in the case of perch (Perca fluviatilis), we can achieve the shortening of the generation interval by shortening the photoperiod simultaneously with the decreasing of the temperature at the right time. Concerning a two-year old pikeperch (Sander lucioperca), we can achieve the same result at a temperature of 12 ° C for the period of three months. In the case of rainbow trout (Oncorhynchus mykiss), early maturation may be best achieved by continuous light in the spring followed by a sudden reduction of the photoperiod together with an increased temperature. In the case of atlantic salmon (Salmo salar), brook trout (Salvenilus fontinalis) and artic charr (Salvenilus alpinus), continuous fotoperiod causes a delay in puberty, however, the increased temperature has a stimulating effect on the onset of puberty for them, too. To sum up the gained information, I conclude that even though one factor may play a primary role on the maturation, other factors also have an impact, sometimes even significant. By manipulating with the above mentioned and other factors, we can achieve a shortening of the generation interval in our fish, which may be the goal of breeders in the Czech Republic and Slovakia.
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Technologie pro účinnou prevenci předčasného dozrávání sivena amerického (Salvelinus fontinalis Mitchill)
LUNDOVÁ, Katsiaryna
Over the past few decades, it has been determined that the period of sexual maturation in salmonids not only has a negative impact on the general condition of fish, but as a consequence reduces the profitability of the aquaculture market as a whole. This influence can manifest itself in reduced growth rate, decreased flesh quality, increased susceptibility to diseases and assumed deterioration of the function of the immune system. Based on these aspects, delaying maturity can be considered a solution to one of the main problems in the on-growth industry. Photoperiod is an important environmental factor that elicits synchronous spawning in salmonids, and thus, as scientific evidence show, it can be effectively used to manipulate the reproduction cycle of fish. The present thesis focuses on effect of various prolonged photoperiod regimes on sexual maturation, growth performance, flesh quality and general physical condition in brook trout (Salvelinus fontinalis Mitchill). In the course of the research, four different experiments were carried out using distinct strategies of the photoperiod. The aim of the first experiment was to test the effects of an artificially prolonged photoperiod using different light sources on brook trout (Chapter 2). The goal of the second experiment was to study the effect of the timing of artificially prolonged photoperiod on growth and sexual maturation of brook trout (Chapter 3). The third experiment aimed to investigate the effects of artificially prolonged non-circadian photoperiod regimes on maturity and growth rate in brook trout (Chapter 4). The fourth experiment focused on the impact of extended photoperiod on post-mortem changes, and sensory, textural and nutritional characteristics of the flesh of brook trout (Chapter 5). Over the course of this research, parameters such as preparedness for spawning, growth rate, hormone level, fillet yield and survival rate, resistance to secondary fungal disease, fin condition and colouration characteristics were studied. Flesh quality of brook trout was analysed via rigor index, pH changes, fillet contraction, gaping, flesh water loss, texture and colour, sensory analysis, and finally fat content and composition analyses. The results of this complex study revealed that the tested artificially prolonged photoperiod regimes positively influence somatic growth. In all experiments, a lower growth rate was observed in control groups, especially during spawning period. Also, it can be assumed that the use of prolonged photoperiod contributes to the delay of sexual maturation in brook trout, regardless of the sex. This statement was confirmed by the analyses of hormones level that showed a similar tendency in all parts of this study. In all of the experiments, a significantly higher number of sexually mature fish ready to spawn were found in the control groups. The results of the flesh quality testing in brook trout (Chapter 5) showed that fish exposed to artificially prolonged photoperiod had a faster progression of rigor mortis, significantly higher fillet contraction, less aftertaste, higher fat content and different fat composition compare to fish from the control groups. The results of this study shed light on the possibility of using photo-stimulation to regulate reproductive cycles and improve growth parameters and the general characteristics of brook trout. These findings can be useful for developing an economically viable culture strategy, thus raising market profitability.
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The effect of the light period on milk yield and fertility of dairy cows
VRBOVÁ, Aneta
The main objective of the study was to ascertain fertility and milk productivity of dairy cows raised under the conditions of modern technology in the context of micro-climactic features and the quality of housing. The observation occurred from 1. 1. 2013 to 31. 12. 2014 in Cooperative Farm Pluhův Žďár and 150 dairy cows of the Holstein cattle were observed. The program Statistica 12 (StatSoft?) was used to evaluate observed values. Data characterisation was conducted through the use of descriptive statistics, and, furthermore, a correlation analysis and a chi-square test were used. During the evaluation of the micro-climate of the stables, it was detected that the average temperatures of the environment shifted from 7.90 °C to 27.03 °C. Relative humidity was measured in the range of 73.44 % and 86.84 %. THI achieved values from 45,11 to 68.93. The milk yield correlated negatively with the temperature during autumn months (r = - 0.377) and a negative correlation was also found in relation to the relative humidity (r = - 0.356) and a similar relation existed between the THI and the milk yield (r = - 0.409). The influence of the length of the photoperiod on milk productivity showed itself to be positive in the cases of all groups of observed dairy cows. The group of cows at the 1st lactation increased milk productivity by 4.7 % the cows at the 2nd lactation showed an increase of milk productivity by 12.6 % and the dairy cows at the 3rd and further lactations provided an increase of milk yield of 18 %. The influence of the length of the photoperiod on conception was not statistically conclusive (p = 0.100), but there was a tendency pointing to worse conception results when automatic lighting was used as opposed to when the natural photoperiod was used. With the temperature on the day of conception taken into consideration, the rate of conception ranged between 27 % and 51 % in the periods of 24 and 48 hours before insemination. There was a tendency of a better conception in the group of primiparous cows in the temperature range over 15.1 °C in comparison with the group of cows at the 2nd and further lactations. The influence of the temperature of the environment on conception after first insemination 24 and 48 hours before the insemination itself was statistically conclusive (p < 0.05). A positive influence of an extended photoperiod on rumination was found among all groups of observed dairy cows. The dairy cows at the 1st lactation increased their ruminative activity by 42 minutes and the group of older cows by 25 minutes in 24 hours. The greatest difference between these two groups was observed during the winter months (XII-II), during which time the dairy cows ruminated longer by 21.7 % on average in comparison with the natural photoperiod (p < 0.001).
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Mechanisms of natural resistance of quinoa to abiotic stresses
Cíza, Marek ; Lipavská, Helena (advisor) ; Hála, Michal (referee)
Quinoa is traditionally grown crop originating from areas adjacent to Andean Mountains in South America, where it is grown by local native population for over 5000 years. Its extraordinal resistance to abiotic stresses as salinity, drought or frost, along with quite exceptional nutritional qualities of the seed, earned it the designation "supercrop" and the year 2013 was even announced by the FAO organization as the International Year of Quinoa. The main aim of this thesis is to identify the main mechanisms responsible for quinoa resistance to frost, salinity and drought. Marginally, this work also focuses on reaction of quinoa against an attack of most common fungal pathogen and also on different sensitivity of quinoa varieties towards the lenght of photoperiods, which are two important factors in expanding the cultivation of quinoa outside the original area.
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The photoperiodism and hibernation
Pařezová, Lucie ; Bendová, Zdeňka (advisor) ; Weissová, Kamila (referee)
Many organisms living in seasonal environments use annual changes in the length of the day for timing of their responses, such as reproduction, migration or hibernation. Hibernation allows animals to survive difficult periods associated particularly with cold temperatures and lack of food resources. This adaptation requires many physiological, morphological and behavioral changes. Some of these changes take longer, so their right timing is crucial. For most hibernators in temperate regions shortening of the photoperiod is the most reliable signal for initiation of these changes. This work describes the transduction of photoperiodic information to the melatonin signal, its effects in the pars tuberalis and the significance of this structure in seasonal physiology. A more detailed description is devoted to hibernation, and in the last chapter there is briefly mentioned photoperiodism in nonhibernating organisms. Powered by TCPDF (www.tcpdf.org)
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Ecological trends in xylem production of woody plants
Tichý, Jan ; Treml, Václav (advisor) ; Schnablová, Renata (referee)
Xylogenesis (wood formation) is one of the most important biological processes on Earth. Woody plants store atmospheric carbon during this process and are thus an essential player in the carbon cycle, and therefore in the interactions of the biosphere and the Earth's climate system. The course of xylogenesis is affected by many factors, the main factors include photoperiod, temperature and water availability. The significance and impact of individual factors on xylogenesis changes with time and place on Earth. The cambium, which by its division forms wood, enters the dormant and active phase during the year. As part of the changes in the activity of the cambium, rings are formed from which it is possible to read the conditions in which the tree was located during the formation of the given tree ring. This characteristic feature of wood is the subject of many studies and can be used to investigate the effects of climate change on xylogenesis.
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Intenzivní chov okounka pstruhového (Micropterus salmoides) v RAS s různým světelným režimem
BOŇKO, Dominik
Largemouth bass (Micropterus salmoides) is one of the species of fish that don´t have a significant position among the species of fish breeded in Czech Republic. However the trend of building aquaculture recirculation systems with warm water comes to the fore. Breeding in these conditions opens up the possibility of introducing new kinds of thermophilic fish species. Largemouth bass definitely belongs to this group. The general factors of successful breeding of largemouth bass are the temperature and purity of the water, the suitable-composed diet and the correct stocking density. This work studies another factor that not only participates in the success of the breeding, but also has influence on the energy expenses of the aquaculture system. It is the effect of photoperiod during breeding. Five experimental groups with three repetitions were created according to the time of lighting (8, 12, 16, 20 and 24 hours of light a day). The experiment lasted 16 weeks. The average water temperature was 24,6 °C. The initial stocking density for all tanks was 20.6 kg . m-3. Fish had an initial average weight of 32.6 +- 2.1 grams. The feed ration was set up at 1% of biomass per day. As a diet were used a floating dry pellets Skretting R-2 Europa 15 F of 2 mm. The feed contained 55 % of protein and 16 % of fat. Fish were fed manually by hand. All groups showed high survival during the experiment (99.4 - 100 %). The best results were achieved by a group of 8 hours with the highest feed conversion (FCR = 0.94 +- 0.06) and the highest growth rate (SWGR = 0.6 +- 0.04 % . day-1). The average individual fish weight of the 8 hour group at the end of the experiment was 64.07 +- 2.82 g. On the other hand, group of 12 hours was the worst with the lowest average individual weight (W= 57.51 +- 1.51 g), growth rate (SWGR = 0.49 +- 0.04 % . day-1) and the lowest feed conversion (FCR = 1.16 +- 0.08). These two groups were significantly different in most production indicators. The pervisceral fat index grew with biomass. The longer the photoperiod, the higher the plasma and ammonia content of lactate. In contrast, glucose content decreased. A longer photoperiod also influenced the higher production of antioxidants.
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Mechanisms of natural resistance of quinoa to abiotic stresses
Cíza, Marek ; Lipavská, Helena (advisor) ; Hála, Michal (referee)
Quinoa is traditionally grown crop originating from areas adjacent to Andean Mountains in South America, where it is grown by local native population for over 5000 years. Its extraordinal resistance to abiotic stresses as salinity, drought or frost, along with quite exceptional nutritional qualities of the seed, earned it the designation "supercrop" and the year 2013 was even announced by the FAO organization as the International Year of Quinoa. The main aim of this thesis is to identify the main mechanisms responsible for quinoa resistance to frost, salinity and drought. Marginally, this work also focuses on reaction of quinoa against an attack of most common fungal pathogen and also on different sensitivity of quinoa varieties towards the lenght of photoperiods, which are two important factors in expanding the cultivation of quinoa outside the original area.
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