Commercial seed lots of onion (Allium cepa L.) of the cultivars Octavia and Eureka were soaked for 12 h in water of the temperature 20• C, then they were exposed to low frequency magnetic eld (20 mT) for 10, 30, and 60 min. The eld was generated using a standard device for magnetic stimulation VIOFOR JPS applied in human medical treatment. Next, the seeds were evaluated for energy and capacity of germination, length of the received germs as well as fresh masses of the obtained seedlings using the routine methods recommended by the International Seed Testing Association. For the seeds of the cultivar Octavia, the eld did not aect the energy of germination, however it did improve in all tested treatments their germination capacity. In the best of them (60 min), the germination capacity increased by 4.6%. For the seeds of the cultivar Eureka, the tested eld increased their energy of germination, which improves evenness of plants emergences in the eld and has a signicant importance for horticultural practice. When the seeds were exposed to the eld for 60 min, their germination energy increased from 40% (control) to 63%. This result was accompanied by no dierences in both length of germs and fresh masses of the received from them seedlings.

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Collagen is the major biopolymer of a living organism, which physical properties depend on water content. The observed transmission of spongiform encephalophaties (BSE) to humans resulted in the development of new sources of collagen. Fish skin seems to be one of such safe sources of collagen. Measurements of electrical conductivity as a function of temperature provides information, among other things, on the water release process. Experiment was carried out for fish skin (FSC) collagen (type I) and bovine Achilles tendon collagen (type I). Each sample was heated two times. Current-voltage characteristic was determined for FSC collagen to determine the range, within which the relation is linear. The primary differences appeared to be in electric conductivity, which was higher for FSC collagen than for BAT collagen. Electric conductivity varied from 10 −6 S/m to 10 −10 S/m depending on material and temperature. The process of free and bound water release was manifested as a peak on electrical conductivity-temperature curve between 320-350 K. The activation energy of the charge conduction process, determined on the basis of the Arrhenius plot, was material dependent and considerably higher for FSC collagen.

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Studies on electric conductivity of collagen indicate the occurrence of percolation threshold, which comprises free release of water and change its properties from semiconducting to dielectric one.