Effects of varying preseed magnetic treatments on growth, chlorophyll pigments, photosynthesis, water relation attributes, fluorescence and levels of osmoprotectants in maize plants were tested under normal and drought stress conditions. Seeds of two maize cultivars were treated with different (T0 [0 mT], T1 [100 mT for 5 min], T2 [100 mT for 10 min], T3 [150 mT for 5 min] and T4 [150 mT for 10 min]) electromagnetic treatments. Drought stress considerably suppressed growth, chlorophyll a and b pigments, leaf water potential, photosynthetic rate (A), stomatal conductance (g(s)) and substomatal CO(2) concentration (C(i)), while it increased leaf glycinebetaine and proline accumulation in both maize cultivars. However, pretreated seeds with different magnetic treatments significantly alleviated the drought-induced adverse effects on growth by improving chlorophyll a, A, E, g(s), C(i) and photochemical quenching and nonphotochemical quenching, while it had no significant effect on other attributes. However, different magnetic treatments negatively affected the g(s) and C(i) particularly in cv. Agaiti-2002 under drought stress conditions. Of all magnetic treatments, 100 and 150 mT for 10 min were most effective in alleviating the drought-induced adverse effects. Overall, preseed electromagnetic treatments could be used to minimize the drought-induced adverse effects on different crop plants.

Alleviation of adverse effects of drought stress on growth and some potential physiological attributes in maize (Zea mays L.) by seed electromagnetic treatment.

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: seed biostimulation, laser radiation, nitrate reductase, chlorophyll, sugar concentration

Impact of presowing laser irradiation of seeds on sugar beet properties

Normally the productivity of cropping systems in arid and semi- arid regions is very low. The sustainable agricultural systems try to fi nd out environmental friendly technologies based on physical and biological treatments to increase crop production. In this study two irrigation treatments (control and water stress) and six methods of fertilizer treatment (control, NPK-F, using magnetic band- M, using silver nano particles- N, M+N and M+N+50% F) on performance of ajowan were compared. Results showed that treatments with magnetic fi eld or base fertilizer had more yield compared to the control and silver nanoparticles (N) treatments. Application of silver nanoparticles had no positive effect on yield. The highest seed and biomass WUE achieved in base fertilizer or magnetic fi eld treatments. Under water stress treatment, seed WUE signifi cantly increased. In conclusion magnetic fi eld exposure, probably by encourage nutrient uptake effi ciency could be applied to reduce fertilizer requirement. On the other hand the cultivation of plants under low MF could be an alternative way of WUE improving.

https://sciendo.com/pdf/10.1515/pjct-2015-0016

Effect of magnetic field and silver nanoparticles on yield and water use efficiency of Carum copticum under water stress conditions

Effect of magnetic field treatments for seeds and irrigation water as well as N, P and K levels on productivity of tomato plants.

A b s t r a c t. The plant seed embryo tissue cell, including the cell membrane and the intracellular and extracellular regions, was modelled as a spherical body. Equations for the three components in spherical coordinates were developed to calculate potassium ions flux in the presence of a stationary magnetic field. Simultaneous mathematical simulations of radial flux for potassium, calcium and chloride ions as well as membrane potential and osmotic pressure were calculated. Results obtained by computerized simulation showed that a magnetic field of 200 mT provoked some changes in cellular ionic concentration with respect to exposure time during first 30 s, which also impacted on the membrane potential and osmotic pressure values. K e y w o r d s: magnetic field, ions, membrane, model, seed

Simulation of magnetic field effect on a seed embryo cell

Pre-sowing treatment of seeds using a low frequency magnetic field (16 Hz, 5mT) and its impact on the yield and quality of plants were investigated. Magnetic treatments increased the emergence of seeds, especially for low vigour seeds. The chlorophyll content also increased significantly. As a result, the yield of plant roots was increased. The magnetic field also influenced the content of sugar in the root of the beet.

A. Ziarnik

Papers

Impact of low frequency magnetic fields on yield and quality of sugar beet