Electromagnetic fields and electromagnetic radiation as non-invasive external stimulants for seeds (selected methods and responses)

Results obtained in research on the effects of EMF (electromagnetic field) and EMR (electromagnetic radia- tion) on seeds and seedlings show that it is still impossible to draw coherent conclusions. The seed is an extremely complex system, and its state cannot always be controlled. Biological processes proceed in parallel and they may react in different directions to an EMF stimulus. Therefore, the fundamental role of the researcher is selection of biological material for the investigations and also of appropriate external conditions for running them. This work fo- cuses on some essential factors that must be considered during the experiments. The knowledge of the parameters of seeds (moisture content, growth rate, storage period) and EMF (field strength, frequency, time of exposure, polarity) as well as environmental parameters (temperature, light, moisture content of soil) is necessary to understand the correlations between the physiology and cytology of the growing seedlings and the electromagnetic stimulus. The classification of parameters and quantities which are determined during the research of the influence of electromagnetic and laser treatment of seeds and some basic equations determining the dose of EMF or EMR absorbed by seeds are also presented. K e y w o r d s: pre-sowing stimulation, magnetic field, electric field, laser radiation