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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.

The aim of the present work, based on two experiments, was to evaluate the impact of photostimulation as a prevention for delaying the sexual maturation of brook trout (Salvenilus fontinalis). Another additional experiment was to describe which effect has photostimulation on the consequences of aggressive behaviour of males. Two experimental groups were established and differed in illumination sources: the metal halide lamps (HAL) and the light emitting diodes (LED). The photostimulation timing (photoperiod) was tested in following experiment. In both tested groups (HAL and LED) the photoperiod was prolonged to 18L:6D in comparison to the control group with natural photoperiod. The results shows that before spawning females and males in both tested groups (HAL and LED) reached significantly higher body weight up to 100 g (=0.05) due to desirable delayed sexual maturation (up to one month). By obtaining the same results in both groups, clearly profitable source of illumination was LED and the time for sufficient application before spawning was 67 days. Moreover photostimulation had also positively reflected in the elimination of aggressive behaviour of males. The results of the present study suggest that photostimulation may be applicable in the intensive culture systems of salmonids in the Czech Republic.

The aim is to determine the importance of photoperiod for oviposition of Peruphasma schultei. The theoretical part covers common description of the reproduction and embryonic development of phasmid. Included the climatic factors affecting physiological action and brief description of the biological clock of insects. Experimental individuals were are kept in three different photoperiods with constant temperature of 25 °C. Control and collection of eggs ran at intervals of two hours. It was shown the influence of photoperiod, time and their interaction on the number of eggs and imposed the difference in putting across time.

Light is one of the main environmental factors largely determining plant life. Light provides energy resources for photosynthesis and it is also the most important medium of perception as it represents the main source of information about plant surroundings. My diploma thesis entitled “Light and its effect on plant proteome” briefly summarizes present knowledge about the light perception in plants, its interpretation of light quality, quantity, and direction via photoreceptors. These components trigger a whole range of changes, both on molecular and developmental levels, but the complex molecular mechanisms regulating system of light signalling in plants are far from being resolved. Here, I followed effects of different light parameters on plant proteome, namely, diurnal variations, low- and high-light intensity, spectral composition, and a change in the light period duration. To study these effects two model organisms were selected (i) Arabidopsis thaliana as a representative plant model with the most annotated genome/proteome and (ii) Solanum lycopersicum as a representative plant model significant for agriculture and biotechnology. Proteome changes in response to different light factors were analyzed by LC-MS. In total, the analyses revealed over 100 and 300 light-responsive proteins in Arabidopsis and S. lycopersicum, respectively. Proteomics provided highly sensitive snapshots of protein abundance in response to light and selected experiments have been complemented with a GC-MS metabolite profiling, conductivity measurements, and fluorescence microscopy.

Wing polymorphism of semiaquatic bugs is affected by environmental factors as temperature, photoperiod, population density or permanency of habitat. The heritability has its own specific part, too. A lot of field studies suggest that crucial effect on wing polymorphism has temperature, but laboratory experiments often do not confirm this hypothesis. The main aim of this thesis was to describe the effect of environmental factors (photoperiod, temperature and permanency of habitat) on wing polymorphism of Microvelia reticulata, additionally of Gerris lacustris. The partial tasks included description of effect of mentioned abiotic factors on mortality and rate of development. The individuals of both species were kept at combinations of two levels of temperature, photoperiod and permanency of habitat (overall at eight treatments) from first larval instar to adult. All adults of Microvelia reticulata emerged as apterous, so there was no response of wing polymorphism to tested environmental factors. The main influence of heritability is presumable. Only ten individuals of G. lacustris developed into the adult stage, so it was impossible to describe the influence of abiotic factors on wing polymorphism, mortality and lenght of development in this species. Mortality of individuals of M. reticulata was significantly influenced by the type of substrate. Only 3.5% of individuals survived when reared on wet filter paper, while 80.5% on the water surface. Both other factors (temperature, photoperiod) had no effect on total mortality. There was no difference between mortality of males and females, so it is impossible to note sexual dependent mortality. The lenght of development did not differ between sexes either. Lenght of development was significantly affected by temperature, as low temperature reduces development of M. reticulata. The fastest development showed nymphs of second instar and slowest development nymphs of fifth instar at all treatments. Since the effect of abiotic factors on wing polymorphism was not found in M. reticulata, it would be sufficient to study the effect of heritability on development of wings in this species in the future.