A b s t r a c t. The aim of the experiment was to establish the influence of biostimulation on the sugar beet seeds. The seeds came from the specialized breeding program energ'hill or were irradiated by the laser in two doses. The impact of the biostimulation was analyzed by determining the nitrate reductase activity and the nitrate, chlorophyll and carotenoids contents in leaves, as well as, the dry matter and sugar concentration in mature roots. The field experiment was established for two sugar beet cultivars. Biostimulation by irradiation and a special seed breeding program energ'hill had a positive influence on some examined parameters (particularly on nitrate reductase activity in Ruveta and in numerous cases on photosynthetic pigments in both cultivars). Regarding the dry matter accumulation and sugar concentration this impact was more favourable for Tiziana than for Ruveta cultivar.K e y w o r d s:

A b s t r a c t. Germination and sugar beet yield after seed stimulation were investigated. The seeds came from the energ'hill technology and were subject to laser irradiation. The experiments were conducted in the laboratory and field conditions. Lengthening of germinal roots and hypocotyls was observed. A positive effect of the stimulation on the morphological features was observed for the Eh seeds and laser irradiation applied in a three-fold dose. The energ'hill seeds exhibited a significantly higher content of carotenoids in seedlings and an increase in the content of chlorophylls. Laser light irradiation favourably modified the ratio of chlorophyll a to b. The leaves and roots of plants developed from the energ'hill and irradiated seeds were characterized by higher dry matter content thanin non-stimulated seeds. Seed stimulation had a positive influence on yielding and the saccharose content.K e y w o r d s: sugar beet, seed stimulation, germination, yield

The aim of this study was to evaluate the effect of pre-sowing seed treatments on some agro-physiological parameters of sugar beets. The selected seed treatments were laser stimulation, hydropriming and a combination of hydropriming and laser irradiation. The impact of the stimulation of seeds was analysed by determining the acid phosphatase activity, concentration of phosphate and photosynthetic pigments in leaves as well as the nutrient status and some yield parameters of the roots. The plants were assayed four times during the growing period. The experiment showed that the priming methods had a relatively small effect on both the level of orthophosphate and total phosphorus concentration. On the other hand, the plants raised from seeds both hydro-and laser-primed preserved a more stable level of phosphates during the whole growing season than the other plants. The highest activity of acid phosphatase was observed in younger plants and among different seed treatment, plants grown from non-primed seeds and laser-primed seeds showed the highest enzyme activity. In later growth stages, enzyme activity lowered considerably. Considering the effect of different seed treatments, a significant increase in enzyme activity was observed in plants emerged from hydroprimed or laser stimulated seeds. In addition, an increase in chlorophylls occurred in plants emerged from hydroprimed seeds and from hydro-and laser-primed ones. Seed stimulation had a positive effect on the potassium content, particularly in leaves of sugar beet, and on some yield parameters of the roots. Concluding, the effect of pre-sowing seed stimulation (priming) was visible during the entire growing season. Out of the examined seed treatment methods, hydropriming alone or in combination with laser radiation caused the highest alterations in the assayed parameters.

The changes of chemical composition and sucrose content in sugar beet beet after seeds stimulation were investigated. The seeds came from the energ'hill technology (Eh) and were subject to laser irradiation. The experiments were conducted in the laboratory and in field conditions in 2008-2010. In the experiment the researchers used the seed material of Tiziana variety (sugar type) in standard version (control) and stimulated: prepared in the energ'hill technology and irradiated. Irradiation with laser light was applied in the following doses: the 5-time multiplied (in the study marked as D5) and 7-time multiplied (in the study D7) of the basic dose 2.5 10-1 J cm-2. The content of nitrogen, phosphorus, potassium, sodium, magnesium and calcium in leaves and roots samples collected in the first weeks of July, August, September and October. Pre-sowing stimulation with use of energ'hill technology and laser light irradiation resulted in an increase in leaf concentration of nitrogen, potassium, sodium and magnesium and the content of these elements positively correlated with sucrose content of mature roots. Pre-preparation (sprouted) clusters energ'hill technology and laser irradiation had a positive effect on sucrose content and its performance.

The aim of this work is to compare the effect of three- and sixfold irradiation with a semiconductor laser beams of 200 mW power and wavelength equal to 670 nm and the rooting agent on the percentage and quality of rooted cuttings of leatherleaf viburnum. The most effective for root number and root length was threefold irradiation and for fresh root weight threefold irradiation applied together with the rooting agent.