Changes in the intensity of selected physiological, biochemical and molecular processes caused by the simultaneous effect of soil compaction stress and soil drought in individual maize hybrids differing in the degree of sensitivity to these stresses

Ecological and economic effects caused by drought, flooding are globally significant and is confirmed by the fact that climatic anomalies occur more frequently now, which may be related to climate change and manifest among others increase in average temperature and fluctuations in the size and distribution of rainfall. In Poland, more often we have to deal with droughts, which includes large areas of crops, while the phenomenon of soil waterlogging are more local in nature and concern incidental flooded areas during a flood or as a result of prolonged heavy rainfall.

It is necessary to conduct intensive research to prevent the risk of a food crisis caused by the limitation of useful agricultural land, increase in production costs and prices and earmarking part of the crop to biofuel production. It seems that the possibility of increasing crop yields by increasing expenditure on fertilizers and plant protection have been exhausted, and progress can be achieved by “biological progress”  on the introduction of varieties with increased resistance to stress. A perfect example is the "Green Revolution", which not only eliminated the famine in Asia but has done, that the traditionally regarded as poor (India, China) have become significant importers of wheat and rice.
Currently, the breeding of plants resistant to different abiotic stresses used in physiological and molecular markers. Physiological markers assist the selection of plants having a matching character but it is a task work and time consuming, it requires much experiments, taking into account the different phases of plants growth and  environmental conditions. In contrast, the molecular markers are more versatile because they do not become altered by environmental factors and the selection is independent of the development phase of the plant. Modern molecular biology techniques used in the preparation of new varieties with desirable traits are greater than the traditional methods in terms of ease of use and speed of obtaining the desired effects. Extensive use of molecular methods in breeding especially in obtaining genetically modified crops (GMO), but this creates a certain risk constraints natural biological biodiversity and why it is common to formation of gene banks to store seeds of species and varieties that could eliminated in the environment.

The topics of planned research it is important because it allows to evaluate genetically variability of environmental stresses and to identify harmful effects of human activities to the agricultural environment. Maize is an interesting research model because is characterized by high genetic variability and has a significant economic importance. Growth, development and productivity of plants depends on their genetic potential and the currently prevailing climate and soil environmental conditions. Genetically determined traits are characterized by high plasticity and is used in breeding work. The environmental conditions are highly volatile. Unfavourable to plant the course of action of these factors are called abiotic stresses and they cause adverse effects which may even lead to plant death. In natural environments frequently we have to deal with the situation of simultaneous occurrence of different stress (multistress effect) therefore a key objective of the research will be to determine changes in the rate of physiological processes in different genotypes of maize growing under different soil compaction and treated of soil drought stress or soil waterlogging.