The challenges facing modern plant production involve (i) responding to the demand for food and resources of plant origin from the world's rapidly growing population, (ii) coping with the negative impact of stressful conditions mainly due to anthropopressure, and (iii) meeting consumers' new requirements and preferences for food that is high in nutritive value, natural, and free from harmful chemical additives. Despite employing the most modern plant cultivation technologies and the progress that has been made in breeding programs, the genetically-determined crop potential is still far from being fully exploited. Consequently yield and quality are often reduced, making production less, both profitable and attractive. There is an increasing desire to reduce the chemical input in agriculture and there has been a change toward integrated plant management and sustainable, environmentally-friendly systems. Biostimulants are a category of relatively new products of diverse formulations that positively affect a plant's vital processes and whose impact is usually more evident under stressful conditions. In this paper, information is provided on the mode of action of a nitrophenolates-based biostimulant, Atonik, in model species and economically important crops grown under both field and controlled conditions in a growth chamber. The effects of Atonik on plant morphology, physiology, biochemistry (crops and model plant) and yield and yield parameters (crops) is demonstrated. Effects of other biostimulants on studied in this work processes/parameters are also presented in discussion.

Fruits of transgenic cucumber lines expressing preprothaumatin II gene were evaluated concerning their aroma. Four homozygous lines, that is, 210 06, 212 01, 224 09, and 225 03 with different levels of transgene expression were selected. Recipient line cv. Borszczagowski, which was formed by inbred line of Cucumis sativus L., was used as a control. The experiment was carried out in a greenhouse and an outdoor experimental plot. The aroma of cucumber fruits was evaluated by GC/MS, as well as GC/MS/TOF in the distillates and by SPME. Irrespective of the isolation/separation technique used, the differences between aroma compounds in transgenic cucumbers and the control were quantitative, and not qualitative. Modified samples showed higher concentrations of volatiles, particularly of the main cucumber fruits odorant (E, Z)-2,6 nonadienal. Transgenic expression of the thaumatin II gene resulted not only in a sweeter taste of fruits in comparison with the control, but also higher aroma acceptability. This was shown by sensory profile analysis. Also electronic nose measurements differentiated between transgenic lines and the control.

Light is one of the most important limiting factors for photosynthesis and the production of plants, especially in the regions where natural environmental conditions do not provide sufficient sunlight, and there is a great dependence on artificial lighting to grow plants and produce food. The influence of light intensity, quality, and photoperiod on photosynthetic pigments content and some biochemical and growth traits of cucumber seedlings grown under controlled conditions was investigated. An orthogonal design based on a combination of different light irradiances, ratio of LEDs and photoperiods was used. Treaments consisted of three light irradiance regimes (80, 100, and 150 µmol m−2 s−1) provided by light-emitting diodes (LEDs) of different ratios of red and blue (R:B) (30:70, 50:50, and 70:30) and three different photoperiods (10/14, 12/12, and 14/10 h). The white light was used as a control/reference. Plant height, hypocotyl length, stem diameter, leaf area, and soluble sugar content were highest when exposed to LM9 (150 µmol m−2 s−1; R70:B30; 12/12 h) light mode, while the lowest values for the above parameters were obtained under LM1 (80 µmol m−2 s−1; R30:B70; 10/14 h). Higher pigments contents (chlorophyll a, chlorophyll b, and carotenoid) were obtained when light regime LM9 (150 µmol m−2 s−1; R70:B30; 12/12 h) was applied. In general, cucumber seedlings grown under the LM9 regime showed a significant increase in growth as well as photosynthetic capacity. It seems that the content of photosynthetic pigments is the key factor responsible for the performance of cucumber seedlings grown under different lighting modes, compared to other traits studied. We recommend monitoring the content of chlorophyll a, b, and their ratio value when studying the light requirement of cucumber plants.

Light is one of the basic factors needed by plants for their development. The aim of this study was to measure the effect of supplementary lighting of tomato plants with HPS and LED lamps on the chosen physiological parameters and yielding of autumn-winter cultivation crops. Two tomato cultivars ('Komeett' F 1 and 'Starbuck' F 1 by De Ruiter Seeds) were used in this experiment. After the plants were planted, LED and HPS lamps of 100 µmol m -2 s -1 light intensity were installed. The results show that the introduction of a supplementary light source to tomato cultivation caused an increase in the intensity of photosynthesis, transpiration, stomatal conductance and chlorophyll by 57.7%, 17.1%, 39.3% and 24.4% on average, respectively. Higher values of those parameters were obtained with HPS lamps than with LED lamps. The amount of marketable crops, number of fruits and mean fruit weight were higher in both combinations in which supplementary lighting was applied, and the values of these traits were higher when the cultivation was supplementary lighted with HPS lamps than with LED lamps. Due to the overhead light configuration and continued low light output, there was no increase of efficiency when using LED lamps compared to HPS lamps despite better focusing and spectral distribution.

were used in the study. Seeds were sown at the end of March and transplants were grown in a greenhouse. The plants were grafted on Maxifort F 1 rootstock on April 5, 6 and 21 in the years 2006, 2007, 2008 respectively without the use of biostimulators. In the case of the other combinations each year the following treatments with biostimulators were performed: watering with Goteo 0.1% solution (twice -4 and 2 weeks before planting and three times after planting at three-week intervals), spraying with BM 86 0.1% solution (four times every three weeks starting at the blooming of first cluster). In the control combination plants were neither-nor grafted or treated with biostimulators. Plants were planted in the field at 70 x 100 cm spacing -20 plants per plot. For the ripe fruits analyses the following parameters were determined: dry matter, total sugars, vitamin C, carotenoids and macroelements: N, P, K, Ca.A higher total and marketable yield was obtained after grafting and Goteo treatments. There was a significant influence of grafting and the application of the biostimulators on the content of dry matter and total sugars, however, the highest content of vitamin C and carotenoids were obtained in the control. There was a slight increase of the content of nitrates and calcium in the fruit in the case of grafting and Goteo biostimulator watering treatments, whereas the highest content of potassium in the fruit was obtained in plants treated with BM 86 and phosphorus in the fruits from control combination plants.