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Changes in gas exchange of selected genotypes of poppies depending on the influence by low temperature
Málek, Jan ; Hnilička, František (advisor) ; Orsák, Matyáš (referee)
The Czech republic is one of the biggest Opium poppy producers. In 2015, this plant was grown in an area of approx. 32 650 ha. Since the poppy is usually sown quite soon in the spring, it can be damaged (or negatively affected) by low temperatures. The main objective of this Bachelor thesis was to determine the speed of gas exchange in several poppy species affected by low temperatures.
In this research, altogether 12 various genotypes of Opium poppy (Papaver somniferum L.) were included in (development phase 35 BBCH). These were concretely following poppy species: CM 112, Sokol, Major, Opál, Florián, Albín, Postomi, Marianne, Budha, Lazur, Aplaus and Orbis. Under controlled conditions of a clima-box (Conviron), the plants were exposed (within 1 week) to daily temperatures of 10 °C and night temperatures of -5 °C. After one week, the night temperature was increased to 5 °C, while the daily temperature remained the same (i.e. 10 °C). In following two weeks, there was measured the photosynthesis- and transpiration- speed (using the infrared gas analysator LDpro+SD).
Base on measurements made, there was stated, that there could be noted quite big differences in photosynthesis- and transpiration- speed in particular poppy genotypes involved. This fact proves the existency of obvious differences in gas exchange speed of particular poppy species included in this research. Between the particular measurement terms, there could be also noted differences in photosynthesis- and transpiration speed, which proves the influence of low temperatures on photosynthesis- and transpiration speed.
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Formation of yield and dry matter with genetic resources of opium poppy (Papaver somniferum L.)
Slowiaczek, Lukáš ; Hnilička, František (advisor) ; Jan, Jan (referee)
Diploma thesis with the topic: Formation of yield and dry matter with genetic resources of opium poppy (Papaver somniferum L.) was worked out at the Department of botanics and plant physiology, Faculty of agrobiology, food and natural resources ČZU in Prague. The purpose of this thesis was to determine genotype and ontogenetic differences in amount of yield, production of dry mass, and value of growth-analytic characteristics in certain species of opium poppy. Diploma thesis was based on the fact that most of the studies about opium poppy (Papaver somniferum L.) are focused on the content of alkaloids and other substances present in poppy seeds. Due to this facts, it is necessary to describe the genotypes of poppy plants and their genetic resources from the physiological point of view.
Following species of opium poppy were chosen for the experiment: Akvarel, Albín, Buddha, Florian, Korneuburger Weisser, Lazur, Major, Marianne, Opál, Postomi, Sokol, Tatranský. These species were chosen according to their content of alkaloids, especially morfine very low content, low content, medium content and high content of morfine. All of the tested genotypes are tested as object of study of genetic poppy resources. Seeds were supplied by GB Oseva Pro s.r.o., o.z. VÚO Opava and company Český mák.
Field experiments were established at the research laboratory FAPPZ ČZU in Prague, in Červený Újezd. This location is in Prague-West division, in area of Middle Bohemia. The altitude of this location is 401 metres above the sea level. The size of the field for testing was 2 m2. The experiment was based in 4 repetitions by the method of Latin square. Winter wheat was used as the preceding crop. Opium poppy was planted according to agrotechnical principles of planting.
Content of dry mass in individual plant organs was measured in certain ontogenetic stages of opium poppy (35, 45, 49, 52, 54, 62, 81 BBCH). Size of leaf area was assessed by the image analysis WinDias. Yield of seeds was assessed as well. Growth-analytic characteristics were calculated from the values of wieght of dry mass and size of leaf area.
The results confirmed that the size of plants is influenced by its ontogeny and also by its species. The results also confirm, that the height of plants is not influenced by the content of morfine. Connection between the colour of seeds and height of plant was not confirmed either. Increase in weight of above-ground biomass depending on ontogenetic stage and influence of plant species was confirmed. There are differences in production of yield in species of poppy with different contents of morfine because the average weight of yield in species with very low content of morfine was 112,36 g, in species with low content of morfine 110,41 g, in species with middle content of morfine 12167 g and in species with high content of morfine 123,16 g. It was approved that ontogeny of plants influences the leaf area index (LAI) as it increases until blooming and then it decreases as a result of senescence and falling off the old leaves. Differences in leaf area index were detected among the species of opium poppy, depending on the content of morfine. It was detected that crop growth rate (CGR), relative crop growth rate (Rw) and relative growth rate of assimilation area (RA) are influenced by the ontogeny of plants. It was detected that species with high content of morfine in poppy seeds (Buddha, Postomi, Lazur) and species with white seeds Sokol and Albín have lower yield than species with middle content of morfine.
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The analysis of the weather impact on the shape and shift of the production frontier
Hřebíková, Barbora ; Čechura, Lukáš (advisor) ; Peterová, Jarmila (referee)
Although weather is a significant determinant of agriculture production, it is not a common practice in production analysis to investigate on its direct impact on the level of final production. We assume that the problem is methodological, since it is difficult to find a proper proxy variable for weather in these models. Thus, in the common production models, the weather is often included into a set of unmeasured determinants that affects the level of final production and farmers productivity (statistical noise, random error). The aim of this dissertation is to solve this methodological issues and find the way to define weather and its impacts in a form of proxy variable, to include this variable into proper econometric model and to apply the model. The purpose of this dissertation is to get beyond the empirical knowledge and define econometric model that would quantify weather impacts as a part of mutually (un)conditioned factors of final production, to specify the model and apply it. The dissertation is based on the assumption that the method of stochastic frontier analysis (SFA) represents a potential opportunity to treat the weather as a specific (though not firm-controllable) factor of production and technical efficiency. SFA is parametric method based on econometric approach. Its starting point is the stochastic frontier production function. The method was presented in the work of Aigner, Lovell and Schmidt (1977) and Meusen and van den Broeck (1977). Unlike commonly used econometric models, SFA is based on analysis of production frontier that is formed by deterministic production frontier function and the compound error term. The compound error term consists of two parts -- random error (statistical noise, error term) and technical inefficiency. Technical inefficiency represents the difference in the actual level of production of the producer, and the maximum attainable (possible) level that would be achieved if the producer used a particular combination of production factors in a maximum technically efficient way. Over time, it has been developed on a number of aspects - see time variant and invariant inefficiency, heteroscedasticity, measurement and unmeasured heterogeneity. Along with the DEA, SFA has become the preferred methodology in the area of production frontier and productivity and efficiency analysis in agriculture. Lately, it has been applied for example by Bakusc, Fertő and Fogarasi (2008) Mathijs and Swinnen (2001), Hockmann and Pieniadz (2007), Bokusheva and Kumbhakar (2008) Hockmann et al. (2007), Čechura a Hockmann (2011, 2012), and Čechura et al. (2014 a, b). We assume that the weather impacts should be analysed with regard to technical efficiency, rather than as a part of statistical noise. Implementation of weather in part of deterministic production function rather than in the statistical noise is a significant change in the methodical approach within the stochastic frontier analysis. Analysis of the weather impacts on the changes in the level of TE has not been greatly recorded in the associated literature and is, therefore, considered as the main contribution of this work for the current theory of production frontier estimation, or the technological effectiveness, in the field of agriculture. Taking into account other variables that are important for the relationship and whose inclusion would enhance the explanatory power of the model was part of the objective of this work.Thus, the possible effect of heterogeneity was taken into account when models were formulated and final results discussed. The paper first defined and discussed possible ways how to incorporate the effects of the weather into production frontier model. Assessing the possibility of inclusion of weather in these models was based on the theoretical framework for the development of stochastic frontier analysis, which defines the concept of technical efficiency, distance functions theory, stochastic production function theory and the methodology and techniques that are applied within the framework of SFA, which were relevant for the purpose of this work. Then, the weather impacts on the shape and shift of production frontier and technical efficiency of czech cereal production in the years 2004-2011 was analyzed. The analysis was based on the assumption that there are two ways how to define variables representing weather in these models. One way is to use specific climatic data, which directly describe the state of the weather. For the purpose of this thesis, the variables mean air temperature (AVTit) and sum of precipitation (SUMPit) in the period between planting and harvest of cereals in the individual regions of Czech republic (NUTS 3) were selected. Variables were calculated from the data on monthly mean air temperatures and monthly sums of precipitation on the regional levels provided by Czech hydro-meteorological institute CHMI. Another way to define weather variable is to use a proxy variable. In this dissertation, the calculation of climatic index (KITit) was applied. Climatic index was calculated as a sum of ratios between the actual yield levels and approximated yield levels of wheat, barley and rye, weighted by the importance of each plant in a cereal production protfolio in each region of the Czech republic. Yield levels were approximated by the linear trend functions, yield and weights were calculated with the use of data on regional production and sown area under individual grains by year at the level of regional production (NUTS 3) provided by Czech Statistical Office. Both ways of weather definition are associated with some advantages and disadvantages. Particular climatic data are very precise specificatopn of the actual weather conditions, however, to capture their impacts on the level of final production, they must be implemented into model correctly along with the number of other factors, which have an impact on the level of final production. Climatic index, on the other hand, relates the weather impacts directly to the yield levels (it has been based on the assumption that the violation from yield trends are caused by the weather impacts), though, it does not accomodate the concrete weather characteristics. The analysis was applied on unbalanced panel data consisting of the information on the individual production of 803 producers specialized on cereal production, which have each the observations from at least two years out of total 8-years time serie. Specialization on crop production was defined as minimum 50% share of cereal production on the total plant production. Final panel consists of 2332 observations in total. The values of AVTit, SUMPit a KITit has been associated with each individual producer according to his local jurisdiction for a particular region. Weather impacts in the three specified forms were implemented into models that were defined as stochastic production frontier models that capture the possible heterogeneity effects. The aim is to identify the impact of weather on shift and shape of production frontier. Through the defined models, the production technology and technical efficiency were estimated. We assume that the proposed inclusion in weather impacts will lead to a better explanatory power of defined models, as a result of weather extraction from a random components of the model, or from a set of unmeasured factors causing heterogeneity of the sample, respectivelly. Two types of models were applied to estimate TE - Fixed management model (FMM) and Random parameter model (RPM). Models were defined as translogarithmic multiple-output distance function. The analyzed endogene variable is cereal production (expressed in thousands of EUR). Other two outputs, other plant production and animal production (both expressed in thousands of EUR) are expressed as the share on cereal production and they appear on the right side of the equation together with the exogene variables representing production factors labour (in AWU), total utilized land (in acres), capital (sum of contract work, especially machinery work, and depreciation, expressed in thousands of EUR), specific material (represented by the costs of seeds, plants, fertilisers and crop protection, expressed in thousands of EUR), and other material (in thousands of EUR). The values of all three outputs, capital, and material inputs were deflated by the the country price indexes taken from the EUROSTAT database (2005=100). In Random parameter model, heterogeneity is captured in random parameters and in the determinants of distribution of the technical inefficiency, uit. All production factors were defined as a random parameters and weather in form of KITit enters the mean of uit and so it represents the possible source of unmeasured heterogeneity of a sample. In fixed management model, heterogeneity is defined as a special factor representing firm specific effects, mi. This factor represents unmeasured sources of heterogeneity of sample and enters the model in interaction with other production factors and the with the trend variable, tit.Trend variable represents the impact of technological change at a time t for each producer i. The weather impacts in form of variables AVTit a SUMPit is, together with production factors, excluded from the set of firm specific effects and it is also numerically expressed. That way weather becomes a measured source of heterogeneity of a sample. Both types of models were estimated also without the weather impacts specification in order to obtain the benchmark against which the effects of weather impacts specification on production frontier and technical efficiency is evaluated. Easier interpretation of results was achieved by naming all five estimated models as follows: FMM is a name of fixed management model that does not include specified weather variables, AVT is a name for fixed management model including weather impacts in form of average temperatures AVTit, SUMP is name of model which includes weather impacts in form of sum of precipitations SUMPit, RPM is random parameter model that does not account for weather impacts, KIT is random parameter model that includes climatic index KITit into the mean of inefficiency. All estimated models fullfilled the conditions of monotonicity and kvasikonvexity for each production factor with the exception of capital in FMM, AVT, SUMP and RPM model. Violating the kvasikonvexity condition is against the theoretical assumptions the models are based on, however, since capital is also insignificant, it is not necesary to regard model as incorrect specification. Violation of kvasikonvexity condition can be caused by the presence of other factor, which might have contraproductive influence on final production in relation to capital. For example, Cechura and Hockann (2014) mention imperfections of capital market as possible cause of inadequate use of this production factor with respect to technological change. Insufficient significancy of capital can be the result of incorrect specification of variable itself, as capital is defined as investment depreciation and sum of contract work in the whole production process and not only capital related to crop production. The importance of capital in relation to crop production is, thus, not strong enough to be significant. Except of capital are all other production factors significant on the significancy level of 0,01. All estimated models exhibit a common pattern as far as production elasticity is concerned. The highest elasticity is attributed to production factors specific and othe material. Production elasticity of specific material reaches values of 0,29-0,38, the highest in model KIT and lowest of the values in model AVT. Production elasticity of other material reahed even higher values in the range 0,40-0,47. Highest elasticity of othe material was estimated by model AVT and lowest by model KIT. Lowest production elasticity are attributed to production factors labour and land. Labour reached elasticity between 0,006 and 0,129 and land reached production elasticity in the range of 0,114 a 0,129. All estimated models displayed simmilar results regarding production elasticities of production factors, which also correspond with theoretical presumptions about production elasticities -- highest values of elasticity of material inputs correspond with naturally high flexibility of these production factors, while lowest values of elasticity of land corresponds with theoretical aspect of land as relativelly inelastic production factor. Low production elasticity of labour was explained as a result of lower labor intensity of cereals sector compared to other sectors. Production elasticity of weather is significant both in form of average temperatures between planting and harvest in a given region, AVTit, and form of total precipitation between planting and harvest in a given region, SUMPit. Production elasticity of AVTit, reach rather high value of 0,3691, which is in the same level as production elasticities of material inputs. Production elasticity of SUMPit is also significant and reach rather high lower value of 0,1489. Both parameters shows significant impact of weather on the level of final crop production. Sum of production elasticities in all models reach the values around 1, indicating constant returns of scale, RS (RSRPM=1,0064, RSKIT=0,9738, RSSUMP =1,00002, RSFMM= 0,9992, RSAVT=1,0018.). The results correspond with the conclusion of Cechura (2009) and Cechura and Hockmann (2014) about the constant returns of scale in cereals sector in Czech republic. Since the value of RS is calculated only with the use of production elasticities of production factors, almost identical result provided by all three specifications of fixed management model is a proof of correct model specification. Further, the significance of technological change and its impact on final production and production elasticities were reviewed. Technological change, TCH, represents changes in production technology over time through reported period. It is commonly assumed that there is improvement on production technology over time. All estimated models prooved significant impact of TCH on the level of final production. All specified fixed management models indicate positive impaact of TCH, which accelerates over time. Estimated random parameter models gave contradicting results -- model KIT implies that TCH is negative and decelerating in time, while model RPM indicates positive impact of TCH on the level of final production, which is also decelerating in time. It was concluded, that in case that weather is not included into model, it can have a direct impact on the positive direction of TCH effect, which can be captured by implementing weather into model and so the TCH becomes negative. However, as to be discussed later, random parameter model appeared not as a suitable specification for analyzed relationship and so the estimate of the TCH impact might have been distorted. The impact of technological progress on the production elasticities (so-called biased technological change) is in fixed management models displayed by parameters representing the interaction of production factors with trend variable. The hypothesis of time invariant parameters (Hicks neutral technological change) associated with the production factors is rejected for all models except the model AVT. Significant baised technological change is confirmed for models FMM and SUMP. Biased technological change is other material-saving and specific material-intensive. In the AVT model, where weather is represented by average temperatures, AVTit, technological change is not significant in relation to any production factors. In both random parameter models, rejection of hypothesis of time invariant parameters only confirms significance of technological change in relation to final crop production. Nonsignificant effect of technological change on production elasticity of labor, land and capital indicates a generally low ability of farmers to respond to technological developments, which can be explained by two reasons. The first reason can the possible complications in adaptation to the conditions of the EU common agricultural market (eg. there are not created adequate conditions in the domestic market, which would make it easier for farmers to integrate into the EU). This assumption is based on conclusion made by Cechura and Hockmann (2014), where they explain the fact that in number of European countries there is capital-saving technological change instead of expected capital-using technical change as the effect of serious adjustment problems, including problems in the capital market.. Second possible reason for nonsignificant effect of technological change on production elasticity of labor, land and capital is that the financial support of agricultural sector, which was supposed to create sufficient conditions for accomodation of technological progress, has not shown yet. Then, the biased TCH is not pronounced in relation to most production factors. Weather impacts (SUMPit, AVTit) are not in significant relation to technological change. Both types of models, FMM and RPM were discussed in relation to the presence of the heterogeneity effects All estimated random parameters in both RPM models are statistically significant with the exception of the production factor capital in a model that does not involve the influence of weather (model RPM). Estimated parameter for variable KITit (0,0221) shows significant positive impact of the weather on the distribution of TE. That way, heterogeneity in relation to TE is confirmed, too, as well as significant impact of weather on the level of TE. Management (production environment) is significant in all three estimated fixed management models. In models that include weather impacts (AVT, SUMP), the parameter estimates indicates positive, slightly decreasing effect of management (or heterogeneity, respectivelly) on the level of final crop production. In model FMM, on the contrary, first and second order parameters of mangement indicate also significant, but negative and decelerating effect of management (heterogeneity) on final crop production. If weather impact is included into models in form of AVTit, or. SUMPit, the direction of the influence of management on the level of final crop production changes. Based on the significance of first order parameter of management, significant presence of heterogeneity of analyzed sample is confirmed in all three estimated fixed management models. As far as the effect of heterogeneity on single production factors (so called management bias) is concerned, the results indicate that in case of model that does not include weather impacts (model FMM) the heterogeneity has positive impact on production elasticities of land and capital and negative effect on the production elasticities of material inputs. In models that account for weather impacts, heterogeneity has negative effect on production elasticities of land and capital and positive effect on the elasticity of material inputs. Heterogeneity effect on the production elasticity of labor is insignificant in all models FMM. In all three estimated models, the effect of heterogeneity is strongest in case of production factors specific and othe material, and, also, on production factor land. In case of FMM model, heterogeneity leads to increase of production elasticity of land, while in AVT and SUMP heterogeneity leads to decrease of production elasticity of land. At the same time, the production elasticity of land, as discussed earlier, is rather low in all three models. This fact leads to a conclusion that in models that accomodate weather impacts (AVT and SUMP), as the effect of extraction of weather from the sources of unmeasured heterogeneity, the heterogeneity has a negative impact on production elasticity of land. It can be stated that the inclusion of weather effects into the sources of unmeasured heterogeneity overestimated the positive effect of unmeasured heterogeneity on the production factor land in the model FMM. Management does not have a significant effect on the weather in form of SUMPit, while it has significant and negative effect on the weather in form of average temperature, AVTit, with the value of -0.0622**. In other words, heterogeneity is in negative interaction with weather represented by average temperatures, while weather in form of the sum of precipitation (SUMPit) does not exhibit significant relation to unmeasured heteregeneity. In comparison with the model that does not include weather impacts, the effect of heterogeneity on the production elasticities has the opposite direction the models that include weather. Compare to the model where weather is represented by average temperature (model AVT), the effect of management (heterogeneity) on the production elasticity of capital is bigger in model with weather represented by sum of precipitations (model SUMP) while the effect of management (heterogeneity) on the production elasticity of land and material imputs is smaller in model with weather represented by sum of precipitations (model SUMP). Technical efficiency is significant in all estimated models. The variability of inefficiency effects is bigger than the variabilty of random error in both models that include weather and models where weather impacts are not specified. The average of TE in random parametr models reaches rather low value (setting the average TE = 54%), which indicates, that specified RPM models underestimate TE as a possible result of incorrect variable specification, or, incorrect assumptions on the distribution of the error term representing inefficiency. All estimated FMM models results in simmilar value of average TE (86-87%) with the simmilar variability of TE (cca 0,5%). Technological change has significant and positive effect on the level of TE in the model that does not specify the weather impacts (model FMM), with a value of 0,0140***, while in the models that include weather in form of average temperatures, or sum of precipitations, respectivelly, technological change has a negative effect on the level of TE (in model AVT = -0.0135***; in SUMP = -0.0114***). It can be stated, that in the model where the weather impacts were not specified, the effect of TCH on the level of TE may be distorted, because the parameter estimate implies also a systematic influence weather in the analyzed period. The effect of unmeasured heterogeneity on the level of TE is significant in all three estimated fixed management models. In models AVT and SUMP, heterogeneity has a positive effect on the level of TE (in AVT = 0.1413 and in SUMP =0,1389), while in the model that does not include weather variable the effect of heterogeneity on the level of TE is negative (in FMM =-0,1378). In models AVT and SUMP, the weather impacts were extracted from the sources of unmeasured heterogeneity, and so from its influence on the level of TE (together with other production factors weather becomes a source of measured heterogeneity). The extraction of the weather from the sources of unmeasured heterogeneity leads to change in the direction of heterogeneity effects on the level of TE from negative (in model where weather was part of unmeasured heterogeneity) to positive. The direct impact of weather on TE is only significant in case of variable AVTit, indicating that average temperatures reduce the level of TE (-0.0622**). Weather in form of sum of precipitations does not have a significant impact on the level of TE. It is evident that incorporating the effects of weather significantly changes the direction of the influence of management on the production of cereals and the direction of influence on the management of production elasticity of each factor in the final model. Analogically with the case of the influence of heterogeneity on the production elasticity of land, it is stated that the weather (included in sources of unmeasured heterogeneity) played a role in the underestimation of the impact of heterogeneity on the overall cereal production. Also, in case that weather was not extracted form the sources of unmeasured heterogeneity would play significant role in underestimation of the effect of heterogeneity on the level of TE. Based on the results of parameters estimates, and on the estimate of average values of TE and its variability, it is concluded, that the effect of inclusion of weather into defined models does not have significant direct impact on the average value of TE, however, its impact on the level of TE and the level of final crop production is pronounced via effects of unmeasured heterogeneity, from which the weather was extracted by its specification in form of AVTit a SUMPit. The analysis results confirms that it is possible to specify the impacts of weather on the shape and shift of production frontier, and, this to define this impact in a model. Results Aaso indicate that the weather reduces the level of TE and is an important source of inefficiency Czech producers of cereals (crop). The model of stochastic frontier produkction function that capture the weather impact was designed, thereby the goal of the dissertation was met. Results also show that unmeasured heterogeneity is an important feature of czech agriculture and that the identification of its sources is critical for achieving higher productivity and higher level of final output. The assumption about significant presence of heterogeneity in production technology among producers was confirmed, and heterogeneity among producers is a significant feature of cereal sector. By extracting weather from sources of unmeasured heterogeneity, the impact of real unmeasured heterogeneity (all that was not extracted from its sources) and the real impact of weather on the level of TE is revealed. If weather was not specified in a model, the TE would be overestimated. Model in form of translogarithmic multiple-output distance function well approximates the relationship between weather, technical efficiency, and final cereal production. Analysis also revealed, that the Random parameter model, which was applied in case that weather impacts were expressed as an index number, is not the suitable model specification due to underestimating of the average level of TE. The problem of underestimation of TE might be caused by wrong variable definition or incorrect assumptions about the distribution of inefficiency term. Fixed management model, on the other hand, appears as a very good tool for identification of weather impacts (in form of average temperatures and sum of precipitations in the period between planting and harvesting) on the level of TE and on the shape and shift of production frontier of czech cereals producers. The results confirm the assumption that it is important to specify weather impacts in models analyzing the level of TE of the plant production. By specification of weather impactzs in form of proper variables (AVTit, SUMPit), the weather was extracted from the sources of unmeasured heterogeneity. This methodical step will help to refine the estimate of production technology and sources of inefficiencies (or, the real inefficiency, respectivelly). That way, the explanatory power of model increase, which leads to generally more accurate estimate of TE. Dissertation has fulfilled its purpose and has brought important insights into the impact of weather on the TE, about the relationship between weather and intercompany unmeasured heterogeneity, about the effect of weather on the impact of technological change, and so the overall impact of weather specification on the shape and shift of production frontier. A model that is suitable application to define these relationships was designed. Placing the weather into deterministic part of production frontier function instead of statistical noise (or, random error, respectivelly) means a remarkable change in the methodical approach within the stochastic frontier analysis, and, due to the fact that the analysis of weather impacts on the level of TE to this extent has not yet been observed in relevant literature, the dissertation can be considered a substantial contribution to current theory of the estimate of technical efficiency of agriculture. The dissertation arose within the framework of solution of the 7th FP EU project COMPETE no 312029.
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The profitability of a passive house building
Lakosil, Jakub ; Hricová, Daniela (advisor) ; Olga, Olga (referee)
The subject of the master thesis is an economic saving of a passive house construction in comparison with particular classic low-energy house. The first part of the thesis discusses the evolution of low-energy houses and classification of these constructions according to their energy consumption. It also discusses the advantages of the passive house constructions and the subsidy system, which is possible to use for houses with very low energy consumption. The practical part initially contains a description of chosen bungalow house, which is classified according to its technical specifications into classic, low-energy and passive. Furthermore, there is a brief description of the houses energy consumption and classification into their respective energy group. The subsidy system, described in the theoretical part, is a source for the detection of the subsidy entitlement of particular model varieties. A brief description of acquisition costs, focused on displaying the differences between the studied varieties, is compiled according to particular budgets. There are calculations of investment and operating costs based on technical and price sources. In the conclusion of the thesis there is an economic evaluation of return on investment of particular model types of the houses.
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Current situation regarding the sources and intake of selenium in European population
Půtová, Lucie ; Čadková, Zuzana (advisor) ; Křivská, Daniela (referee)
This bachelor thesis is focused on the current dietary recommendations and the actual intake of selenium from food for the European inhabitants, divided into 6 appropriate regions. Above all, the thesis deals with the issue of the sources of this element and possible ways of its supplementation. Part of this thesis is also the identification of areas in which there is a risk of low intake of selenium, and at the same time there the reasons for this deficit are adressed.
In the introduction selenium is characterized as a trace biogenic element that has physical and chemical properties, which affect the organism of each individual. Selenium can have a wide range of positive effects, but at the same time, of course, its toxicity needs to be taken into account. For this reason, in this study space was devoted to diseases that selenium may cause in cases of non-compliance with the recommended amount of intake.
The amount of the intake of selenium depends mainly on its content in the soil. The concentration of selenium differs according to the geographical conditions of individual regions, which are described in the main part of this thesis. Each region contains a different amount of selenium in soil and consequently in animal and plant products. According to my knowledge from the study of literature, another very important factors is the availability of certain foods, such as fish, which are rich in selenium and thus greatly increase concentration of selenium in the daily diet for several states. The focus was also given to countries, that don't have food rich in selenium, and thus, continue to seek the best possible form of supplementation.
This thesis shows the total comparison of the daily intake of selenium in the specific states of Europe. The results have shown that the most stable intake of this element occurs on the territory of the South Europe. They are mainly coastal states and there is a very good availability of fish products mentioned before. By contrast, in south-eastern Europe it is evident that due to the low financial possibilities the problem of selenium deficit is not dealt with and it is assumed that there may occurr a decline in intake of this element in the diet.
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The effect of water stress on the content of monosaccharides in potato tubers
Podhorecká, Klára ; Orsák, Matyáš (advisor) ; Hnilička, František (referee)
Bachelor thesis is focused on monitoring of influence on selected metabolites, especially monosaccharides. The first part is devoted to short characterization of potatoes, therefore the importance of this crop, morphology, cultivation and also are described demands of potatoes on environment and nutrition.
In the next section is detailed discussed problems of the chemical composition of tubers with a focusing on carbohydrates. Potatoes are globally consumed and are popular source of carbohydrates. Potatoes are rich in vitamins also, especially in vitamin C, B3 and B6. Potatoes contain a high content of minerals, especially potassium and magnesium, too. As another substances are in potatoes colorants, antioxidants, phenolic and related substances, proteins, and small amount of lipids. It is noted that proteins of the potato tuber are ranked among nutritionally valuable proteins of vegetable origin. Among this proteins is ranked Patatin, which is considered to be a major reserve protein and it is placed in the vacuoles. Substances, which has a negative effect on the human body are called Glycoalkaloids the opposite. Glykoalkaloids are synthesized by plants of the family Solanaceae. The most significant substances in potatoes are alfa-solanine and alfa-chaconine. Value of tubers is primarily determined by their chemical composition, which forms food and raw materials. The contents of sugars in the tubers are relatively low (0,5 % of the original mass), and even though their contents are important both in aspect of manufacturing and in sensory aspect. The main reducing monosaccharides are ranked glucose and fructose, typically with a concentration of 0,15 - 1,5 %. The sugar content significantly affects internal and external quality characteristics especially fried products. Several studies confirm that the accumulation of carbohydrates might help resist extreme stress conditions, especially low temperatures, salinity and water deficiency.
In the next chapter is created summary of stress conditions effects on plants with focusing on potatoes. In plants we can talk about stress, if variability of negative environmental factors exceeds a certain limit. The main theme and also the most limiting factor is deficiency of water in other words water stress. Also were mentioned other factors abiotic and biotic factors marginally.
By effects of stress reaction is created a specific level of adaptive skills. Temporarily it can lead to acclimatization, which increasing the resistance to abiotic stressors. Most of plants are trying to establish the tolerance to stress. In this Chapter were also described changes during storage and during heat treatments of potato, which leads to an undesirable darkening of the tubers. Excessive levels of reducing sugars cause unacceptable browning of fried products.
In the last chapter is described selected methods of determining carbohydrates. These methods are based on reducing properties of sugars, on their condensing reactions by color, measurement of optical activity, measurement of refractive index, separation methods and others.
The methodic of work clarifies the determination of reducing monosaccharides (glucose, fructose), sucrose by the high performance liquid chromatography (HPLC) in four selected varieties of potatoes from harvest of 2015.
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Low- and nonenergy sweeteners
Trnková, Lenka ; Orsák, Matyáš (advisor) ; Hniličková, Helena (referee)
Low- and no-calorie sugar subtistutes are compounds that provide food with its sweet taste. As the term suggests, they have lower or no food energy and usually are characterized by higher sweetness than sucrose. For that reason, these substances are especially used during the treatment of diabetes mellitus, to reduce the energy content of food or in prevention of dental caries.
Natural sweeteners were discovered a long time ago, during the search for sustenance. For example Stevia was used by South American Natives even before the European conquest of the territory. However, the history of artificial sweeteners is not too significant, because it relates to breaking the laboratory rules. That is how saccharin was invented in 1878.
Sugar substitutes are added to food on purpose, adjusting the taste or extending the shelf life of foods. In the EU, every approved sweetener has got an E-code, which is displayed on the label.
Sugar substitutes can be grouped according to their origin, their nutrition value or their chemical structure. This thesis discusses low- and no-calorie sugar substitutes that can be synthetic or natural. Mentioned synthetic sweeteners typically contain less then 21 kJ per portion. These intensive food additives possess many times the sweetness of sucrose. The main representatives of this group are saccharin, cyclamate, acesulfame K, sucralose and aspartame with its derivatives. The group of natural sugar substitutes constits of substances like erythritol, D-tagatose, trehalose, neohesperidin dihydrochalcone, stevioside and thaumatin.
There are some limitations confirmed by expert studies. For example, patients suffering from diabetes mellitus should mainly use synthetic sweeteners, because of their low nutritional value.
Even though in some states certain sweeteners are forbidden, safety studies say that there are no adverse effects, if the recommended daily intake is respected. Sugar substitutes, therefore, can be considered safe.
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Properties of selected varieties of tall fescue and their utilization for Lawns
Zachař, Jakub ; Svobodová, Miluše (advisor) ; Klára, Klára (referee)
Grass and its cultivation is being explored in breeding and maintenance for many years. The theme of this thesis is the evaluation of fifteen varieties Tall fescue (Festuca arundinacea Schreb.), which is a hardy robust species with short underground projections, curled leaf composition, wide, very rigid, reverse side rough and shiny on the cheek and fluted leaves. It tillers extravaginal and creates a dense turf. Its great advantage is the strong root system and certain symbiosis (mutualism) with a fungus of the genus Endophyte Neotyphodium, making it resistant to a variety of stresses. The aim is to detect differences intervarietal Tall fescue (Festuca arundinacea Schreb.), Which the Czech Republic is not yet used in the monitored indicators (coverage, color, texture, height stand in a certain time interval, the overall impression). In the future, we can expect increased demand for socalled. low input lawn, because of their tolerance to drought, high and low temperatures and diseases, and especially due to the low need for inputs.
The next chapter describes the properties of each of the individual varieties of tall fescue ( Festuca arundinacea Schreb . ) , which are: Barcesar , Barfelix , Barlexas , Barleroy , Cochise , Debussy , Fine Lawn, Galatea , Kontiki , Olympic Gold , Rembrandt , Regiment , Starlett , Palladium and Zuzana.
An attempt was founded in late August of 2012 a demonstration and experimental plot in the immediate vicinity of the Czech University of Life Sciences in Prague Suchdol, using 15 varieties of tall fescue (Festuca arundinacea Schreb.). Each variety was planted on a plot measuring 1 x 1 meter (one square meter), while calibrating 35 g per m2 in triplicate. Only varieties Barfelix (BF) were sown only in duplicate. Values are obtained climatic conditions at a given for 2014, 2015 and the long term average. The average temperature for the year 2014 was 10.7 ° C and 2015 it was 10.8 ° C which shows that compared to the long term average for those two years the average temperature of almost 2 ° C higher. Annual precipitation for the year 2014 amounted to 571.4 millimeters, which is more than 45 mm more than the long term average, but the annual rainfall for 2015 was only 370.6 millimeters, which is more than 200 mm less than the long term average . 2015 is generally ranked the driest years ever. Measurements were taken every 14 days and a total of 8 measurements were performed, the first measurements were made on 21 May 2015. Since that date, followed by
a total of 5 measurements, namely to July 21, 2015. After that date, followed by a nearly two month break because of the long lasting droughts. For individual varieties of tall fescue were performed in triplicate measurements of height increase in the crop, according to the method EN 735 933 determination of sward height of natural turf. Furthermore, coverage was measured (resistance to weed) according to method EN 735 930 Method C using the points of the frame. Spot frame was in this case replaced by a string measuring 100 cm long split 5 cm, whereby on each parcelce 1x1m were two repetitions.
Results were evaluated using the statistical program ANOVA (LSD, "alfa" = 0.05). Varieties of Paladium (88.3%), Kontiki (87.5) and Zuzana (87.5%) had the highest coverage demonstrably compared to all other varieties. On the contrary, the worst results in a variety of coverage reached Debussy (82.5%), Barfelix (83.3%) and Regiment (83.3%). Conclusive were the differences between other varieties. Olympic Gold varieties (85.8%), Barleroy (85.8%), Cochise (86.7%) and Barcesar (86.7%) were Although demonstrably inferior varieties of palladium, Kontiki and Susan, but also have a palpably better than varieties Barlexas (84.2%), Fine Lawn (84.2%), Starlett (85%), Rembrandt (85%) and Galatea (85%), but which were thus demonstrably better than varieties Debussy Barfelix and Regiment. Variety Fine Lawn conclusively reached its greatest values in growth rate and height above ground organs. When the average height was 6.4 cm in the dry season, however, showed no increase and vice versa suffered from drought, while significantly lowest results in this regard amounted to a variety of Paladium, which reached an average height of only 4.4 cm, which when mowing to 4 cm represents an average increase of just 0.4 cm. The varieties are fully resistant to stress, in the form of drought and high temperatures (Barfelix, Barlexas, Barleroy, Debussy, Galatea, Rembrandt and Starlett), less tolerant (Cochise, Zuzana) and some show no tolerance and conversely, suffer from drought (Barcesar, Fine Lawn , Kondiky, Olympic Gold, Paladium and Regiment). For all varieties was seen very good recovery after a stressful period.
It has been proven that the different varieties of tall fescue from each other in some respects differ , and a wide choice is thus able to fill in a diverse range of applications tall fescue all various environmental conditions or conditions of intensity of cultivation , while its use is possible in increasingly mentioned system low input grassland.
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Evaluation of food and diet in disease phenylketonuria
Čermáková, Venuše ; Faměra, Oldřich (advisor) ; Renata, Renata (referee)
This diploma thesis pursues the hypothesis, that strict abiding or failures in low protein diet are deciding about the health of patients with phenylketonuria. The goal of the thesis was to evaluate the composition of the diet for selected set of patients from the dietological and nutritious point of view in dependence on individual health condition, to compare the values with the diet of healthy people and to evaluate the availability of special healthcare and nutrition for phenylketonuria patients.
The summary of literature gives informations about phenylketonuria, causes of its origin, metabolism of phenylalanin, diagnostics, possibilities of treatment, risks
of repercussion of not treating, impact of nutrition composition of patients' health and dietological recommendations.
For assessment of the bilance of nutrients and energy in the diet of phenylketonuria patients a group of 10 people was selected with different age, sex and dietary level, 5 people with phenylketonuria a 5 healthy persons. For each person a detailed weekly diet was setup and nutritious intake was evaluated, observed was daily intake of Phe, protein, fat, carbohydrate and energy. For persons with phenylketonuria the nutritious was evaluated
in two steps, with and without usage of medical agent. The values of the patients were compared with healthy persons.
From the results a necessity of using medical amino acid agents was derived, in other case there is a risk of serious deficit of protein intake, for some also of fat and energy.
A complicated situation arises for women with phenylketonuria, who plan pregnancy.
The research implies necessity of strict adherence to low protein diet before conception and frequent monitoring of Phe blood values during pregnancy.
The diet must be compiled cautiosly with considering the individual state of patiens,
a thorough education from childhood to adulthood is recommended. The situation would be simplified with a better approach of the state in the area of compensation the costs for foods, but also additional support for phenylketonuria patiens, to improve especially the availability of special foods for low protein diet and treatment possibility.
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Heat sources for low temperature heating systems
Vyskočil, Petr ; Adamovský, Radomír (advisor) ; Neuberger, Pavel (referee)
The goal of this bachelor´s work is to analyse heat sources which is suitable for low temperature heating systems and to descript of main principles and kinds of this heating. The work is divided in five main parts. The first (most extensive) part is description of the history of heat pump, its principle, working substances and basic sources of low potencional energy. The second part of the work is explanation of principles of condensing boiler and natural gas combustion with regard to combustion efficiency. Basic structural elements are included in third section of this work. Next section is discusion of the author´s view on this issue. Is evident from this work that none of this heating system is better in term of advantages and disadvantages. But intension of thist work is primarily description of this advantages and disadvanages.
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