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The main purpose of the work was to study the linearly polarized light impact on the maize plants development. The other purpose was to confirm the model proposed earlier. The methods used in this work include the development of LED light sources, the polarization parameter (degree of polarization) assessment and statistical analysis. Maize (Zea mays L.) plants, Hansatech FMS 1+ pulsed fluorimeter and software TXP Series Instrumentation were used. Plants were grown under white light (WW) with intensity of 200 µmol m–2 s–1. The morphometric parameters measured on the 21st day demonstrated that maize plants of different varieties grown under linearly polarized light developed better than under non-polarized light conditions. In addition, the fact was confirmed by chlorophyll fluorescence measurements. The mechanism has been proposed to explain significant polarized radiation impact on maize, according to which this impact depends on the shape and arrangement of the leaf epidermal cells. The monocotyledonous maize plants have leaves with an ordered arrangement of epidermal cells in comparison with dicotyledonous plants, which cells placed in chaotic order and have no certain shape. Thus, the maize cells layer can transform linearly polarized radiation into elliptically polarized radiation, thus latter should be more efficiently absorbed by the chiral chromophores of photosensitive structures in underlying photosynthetic cells. [ABSTRACT FROM AUTHOR]

The effect of low-intensity laser light on the optical anisotropy of the epidermis of plant leaves is studied. It is shown that a layer of plant cells of various cultures has an optical activity that can lead to a transformation of the polarization state of laser light and to a change in the nature of its interaction with the molecular system of the cell. The data obtained allow one to ascertain that the degree of polarization may depend on the cell structure and shape of plant epidermal cells. This is an important factor in the interaction of polarized laser light with proteins and enzymes in plant leaf cells, which are characterized by isomerism of physical and chemical properties. [ABSTRACT FROM AUTHOR]

The effect of light-emitting diode (LED) lamps with five different spectra on L. sativa plants (variety Aficion) grown in protected soil conditions was studied. Warm white light (WW) was used as the control (the ratio of blue, green, and red portions in the spectrum was 14 : 48 : 38%). The maximum values of the leaf size and the fresh weight of the aerial parts were found in the RGB group (blue–green–red ratio 32 : 19 : 49%), and the highest values of the dry weight and ash content were in the FS group (blue–green–red ratio 27 : 11 : 62%). The stomatal size and density on the abaxial side of the leaf was the highest in SB plants (blue–green–red ratio 33 : 41 : 38%). This was the most effective combination of parameters in terms of leaf architectonics. An increase in the portion of red light in the spectrum with a decrease in the portion of green light had a positive effect on the development of L. sativa plants, while an increase in the portion of green light in the spectrum positively affected the formation of the stomatal apparatus. [ABSTRACT FROM AUTHOR]

In this study the effect of different monochromatic light modes on rocket (Eruca sativa. Mill.) plant development was evaluated. LED light sources significance increases rapidly at the wide application range and have acquired an important role in plant development. Some morphological parameters of the plants were analyzed. Plants grew in a closed growth chambers where three light intensities (100, 1000, and 1400 μmol m–2 s–1) provided by three types of LEDs developed at the Institute of Automation and Control Processes, Far Eastern Branch, Russian Academy of Sciences: red (R), green (G), blue (B), and photoperiod (light/dark—16/8 h) were used and compared with warm white light (WW) (control) with an energy ratio (%) in the red-green-blue range of R38 : G52 : B10. The performed analyzes showed that the highest values of the shoot fresh weight occurred under R2, G2, and WW3 treatments, respectively. The greatest total leaf area values occurred under WW1, B1, and G2, respectively. The highest dry weight content occurred under WW2, WW3, and R2, respectively. The data showed that the application of B2, G2, R2, and WW3 light modes resulted in an increase in growth and productivity as compared with the other treatments and the control. Thus, the monochromatic blue (B2), green (G2), and red (R2) light modes with 1000 μmol m–2 s–1 intensities were the most favorable for plants development among others and could be used for optimization of plant cultivation. The effectiveness of LEDs developed at the Institute of Automation and Control Processes, Far Eastern Branch, Russian Academy of Sciences is acknowledged. The study showed the importance of plant growth under monochromatic RGB spectra. [ABSTRACT FROM AUTHOR]

The development of tomato plants (Solanum lycopersicum L., variety Bonsai) under illumination with various LED lamps was studied. Four illumination options—warm white (WW) as control, solar box (SB), red–green–blue (RGB), and red–blue (FS)—were used in the experiment. They were characterized by different combinations of blue (B), green (G), and red (R) proportions in the spectrum: 14% B : 48% G : 38% R (WW), 26% B : 41% G : 33% R (SB), 32% B : 19% G : 49% R (RGB), 27% B : 11% G : 62% R (FS). The photon flux density was 150 μmol quanta/(m 2 s). It was found that the difference in the R : G : B ratio in the spectra did not affect the accumulation of raw and dry mass of the aboveground parts and roots and the water and dry matter content in the green parts of plants. However, significant differences in the structure of the stomatal apparatus were found depending on the ratio of the main wavelengths (R : G : B) in the spectrum. The density of stomata distribution on the underside of the leaf was the highest in plants under WW conditions and the lowest in plants under FS conditions; the spectral composition of the latter was characterized by a decrease in the proportion of green illumination by 4 times and an increase in the proportions of red and blue illumination by almost two times. As expected, the size of stomatal guard cells was the largest in plants under FS conditions and the smallest in plants under WW conditions. The values for plants grown under RGB and SB were intermediate between minimum (WW) and maximum (FS) values. The response of plants to an increase or decrease in the proportions of the main wavelengths (R : G : B) in the spectrum in the range of 20–30% was flexible and did not affect changes in habitus but promoted acclimation to uncomfortable conditions through physiological parameters. It is concluded that a large proportion of green in the spectrum can have a certain effect on the accumulation of water and dry matter in the aboveground parts of plants and the structure of the stomatal apparatus. [ABSTRACT FROM AUTHOR]

A feasibility study has been made of the planned railway connection to the mainland Russian Federation and Sakhalin Island based on a comparative analysis of currently available data and calculated characteristics obtained in the course of this study. The research was carried out in the following areas: comparative analysis of cargo transportation along the Vladivostok–Kholmsk route, calculation of payback based on the most modern reporting data, and a comparative analysis of historical projects, recent government documents and existing technical projects. Data of a comparative analysis of cargo transportation in terms of three parameters (distance, travel time, and volume of cargo transportation) of the existing railway-ferry service and the planned railway connection along the Vladivostok–Kholmsk route, taking the characteristics of the ferry service into account, were obtained and used as a basis to draw economic-geographical conclusions. A calculation of the recoupment of the planned railway connection was done according to average statistical information. A comparative analysis was made of the historical projects beginning in 1875, as well as an analysis of recent state documents (plans, strategies, and programs). A comparative analysis was made of the current modern technical projects from the bridge-tunnel alternative and their advantages and disadvantages; on its basis, a technical conclusion was made about the possibility and prospects of construction. [ABSTRACT FROM AUTHOR]

The effect of light emitting diode (LED) light sources with different spectra on Eruca sativa Mill., cv. Dikovina plant development was investigated. Experiments were conducted with four types of LED lamps of our own assembly: solar box (SB), red-green-blue (RGB), red-blue (FS), and warm white (WW) used as a control with an energy ratio in the blue-green-red range of 14% : 48% : 38%. Spectra of SB (26% : 41% : 33%), RGB (32% : 19% : 49%), and FS (27% : 11% : 62%) lamps were used to obtain nine different types of lighting ensuring modification of spectra in the course of growing. The plants exposed to FS-RGB, SB-FS, and RGB-SB light sources were characterized with the greatest values of the shoot fresh weight. Transfer of plants to SB resulted in a decrease in development of the plants root system. Transformation of leaf mesostructure after transfer to SB showed that light conditions therein promoted the formation of leaf structure with lower membrane indexes and deformed mesophyll cells. At the same time, cultivation of plants for 2 weeks in SB with subsequent transfer to FS for 4 more weeks stimulated development of internal assimilatory surface of the leaf with the greatest integral indexes of the outer membrane surface of leaf cells (Ames/A) and chloroplasts (Achl/A) as compared with other treatments. As a result, SB-FS plants produced maximal dry shoots and roots biomass. Without alteration of the lighting pattern, plants from box FS were inferior to control plants (module WW) in parameters of leaf mesostructure and ranked second among other types of treatment. The greatest accumulation of P and Ca was observed in FS-RGB where a maximal percentage of shoots and roots dry matter and the greatest concentration of ascorbic acid were found. Transfer of plants from other boxes to FS caused a decrease in accumulation of macroelements in E. sativa plants. Thus, the dynamic lighting applied for growing of E. sativa plants affected their characteristics and could be used for optimization of plant cultivation. [ABSTRACT FROM AUTHOR]