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On this page we would like to introduce the particular area of interest of our research and also the methods, which we use. As stated in Basic info caption, our research is focused on an assessment of changes in an important physiological process in plants - photosynthesis - and the affection of growth and growth characteristics especially in young developmental stages of plants in response to the polluted environment.
It is well know, that visible changes of negative effect of some external factors in plants follow after changes at the level of
biochemical and physiological processes in cells and tissues of plant body. These internal changes could be caused directly by the efect of a factor or indirectly as a defence mechanism of plant.
But it could be difficult to distinguish these mechanisms of action of each factor. For example in case of potentially toxic chemicals, both mechanisms could be considered.
Photosynthesis is very sensitive and vulnerable on the level of both primary and secondary processes. In case of chemical attack of photosynthetic apparatus
on the level of primary processes, thylakoid membranes in chloroplasts are often injured, but their stability is necessary for good function of these photochemical processes. Individual parts of the apparatus can be also damaged -
photosystems and their parts, light harvesting complexes, electron carreers even the molecules of photosynthetic pigments etc..
The affection of primary processes of photosynthesis could be assessed by means of different methods. The most often used are an assessment of changes in induced chlorophyll fluorescence characteristics
and the determination of Hill reaction activity, known as photolysis of water. For detail information, please follow the links.
Growth responses and Phytotoxicity tests
Pollution in the environment participates on the negative affection of growth and development of plants. Typical problems on polluted sites are
dieing out of single plants or whole populations in serious cases due to their injury by xenobiotics during the growth,
the change in species richness of plant society, when only the most resistant species are able to survive, and in some extreme case
the destruction of whole plant society. Sure it is meaningful to assess, which plants are able to survive in which level of environmental loading by toxicants. In practice these experiments
could be focused on compounds, which are not commonly present in the environment, but their potentially toxic effect can not be ruled out.
The history of intentional testing of toxicity of different compounds for different organisms is relatively short.
Development in this area was started above all in the second half of 20th century, when ecology got on to the important biological sciences
and with it also an interest of mankind in the situation and protection of the environment and human health and new scientific disciplines have been arising like Environmental chemistry or Ecotoxicology.
The aim is to describe the toxicant effects on model organisms and on the basis of these result to evaluate the level of risk for humans for case of some contact with this toxicant.
Essential idea now is to unify, standardize, the methods, how to do these tests because of better comparison of results.
Nowadays the development of toxicity tests has reached a state, when tens of standardized methods are available and special "tox-kit" sets are desinged for the possibility to do some test anywhere and anytime, when needed.