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Glutathione is the most important part of a plant’s antioxidant defense system. Two enzymes are involved in cellular glutathione biosynthesis: glutamylcysteine ligase and glutathione synthetase, of which the latter catalyzes the transfer of glycine to the glutamylcysteine dipeptide. Transgenic plants with an elevated expression level of the glutathione synthetase genes are known to be tolerant to heavy metals. However, our knowledge on their tolerance to other types of the abiotic stress is insufficient. The goal of this study is to produce transgenic tobacco plants with a constitutive expression of the glutathione synthetase gene BnGSHfrom rapeseed and to estimate their growth parameters under the normal conditions, as well as under the effects of salt, drought, and cold stresses. We generate 17 lines of transgenic plants with the rapeseed BnGSHgene under the control of the 35S promoter by agrobacterium-mediated transformation. The transgene presence is confirmed by the PCR and histochemical analysis of the activity of the GUSreporter gene. Twelve lines with the highest expression level of the BnGSHgene are chosen based on the results of RT-PCR. The following morphological parameters are measured: stem height, leaf area, flower length, fresh and dry weights of shoots, and root length. Some transgenic plants demonstrated increased productivity both under normal conditions and under the effect of a high salinity stress. However, no change in the tolerance to drought and cold was observed in the transgenic plants.

The lack of knowledge about the impact on ecosystems has restricted the expansion of genetically modified plants. We review the potential gene flow into the environment due to the cultivation of transgenic oilseed rape. The problem is immediate for this crop as its allogamous weedy relatives are widespread. The main difficulty in assessing the risk is caused by the fluctuation in the hybridization frequencies depending on the transgenes used, the crop’s line and population features, and also the imperfection of current methods of molecular diagnostics. In order to minimize such risks, the preliminary investigation of crosspollination, inheritance, expression, and phenotypical effects of transgenes in hybrids with both their wild and domestic relatives is recommended in all regions where GM-crops are going to be grown. Based on this data, specific measures and recommendations to prevent gene flow can be developed. Domestic GM-crop lines, properly tested in local ecosystems can be grown without any environmental threat.

Hybrid plants were obtained by pollination of a Nicotiana rusticaand Nicotiana tabacumBlack Cuban cultivar with pollen from transgenic Nicotiana tabacumplants of a Petit Havana SR1 cultivar bearing the ARGOS-LIKEand AtEXPA10genes. RT-PCR analysis showed high levels of ARGOS-LIKEand AtEXPA10expression in the hybrids, which resulted in increased sizes of their leaves and stems. The organs of both transgenic and hybrid plants were enlarged due to the enlargement of individual cells. The inheritance was stable, while their phenotypic effects varied from insignificant to levels exceeding those in the parental transgenic plants.

One of the main conditions for achieving the set value of the buildings and structures construction duration is the construction production planning. Due to the fact that the construction process has an uncertain dynamic nature, it is recommended to use probabilistic analytical models to determine such a calculated parameter as the duration. The article proposes a probabilistic model for estimating the duration of construction of buildings and structures on the basis of the normalized Erlang's law of the n-th order. This model allows, by changing the number and duration of work lying on the critical path, to assess the construction project completion probability within the prescribed period.