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Ensuring the technical and technological possibility of regularly obtaining fresh, high-quality plant production in Antarctic stations is an urgent task of our time. This work is devoted to studying the growth and development of leaf vegetable crops and the main quality indicators of their edible parts when grown in the phytotechnical complex greenhouses at the “Vostok” Antarctic station and at the agrobiopolygon of the Agrophysical Research Institute (AFI). The plants, belonging to 13 varieties of 9 types of leaf vegetable crops (arugula, garden cress, cabbage, mustard, leaf radish, leaf lettuce, amaranth, dill, parsley leaf), were studied during five growing seasons at the “Vostok” station and at the AFI agrobiopolygon under controlled conditions (control). The experimental data obtained demonstrate the high productivity of the phytotechnical complex for most of the investigated crops per unit of useful area, with lower costs of electricity and water consumption per unit of production compared with a number of greenhouses at foreign Antarctic stations and greenhouse complexes with controlled conditions located on other continents. Lettuce crops were the most adapted to the growing conditions at the Antarctic station “Vostok”. They did not differ in their evaluated characteristics from the control. All other investigated crops, while not differing in their development rate and quality, had statistically significant (16–61%) decreases in their yield per 1 m2 per year. This may demonstrate the difference in the “genotype–environment” interaction in plants grown at the Antarctic station and AFI agrobiopolygon, probably due to the different barometric pressure and partial pressure of oxygen at the two locations. The positive psychological effects of the greenhouses were identified along with nutritional and other qualities of the plants.

Quick and accurate nondestructive methods of water deficiency detection prior to the appearance of visible symptoms of plant deterioration as well as estimation of photosynthesis parameters are needed to effectively control conditions of plant growth, to manage crop productivity and to implement programs of "smart farming". The aim of our investigation was to analyse spectral characteristics of leaves diffuse reflection as evident in soft spring wheat cultivars (Triticum aestivum L.) of different drought resistance in optimal conditions and under the impact of soil drought; another objective was to determine the reflection indices that could serve as criteria in the phenotyping of genotypes according to their photosynthetic apparatus capacity and the efficiency of light use as well as in the forecasting of genotypes potential productivity and their drought resistance. Wheat plants of 4 drought-resistant and 4 non-resistant cultivars were grown under controlled conditions in the protected ground. In the vessels with simulated soil drought, the moisture content was 30% of total field capacity, while in the control sample it was 80%. Spectral characteristics of radiation reflected from the leaf surface were recorded with the spectrometer HR2000, and then reflection indices were calculated whose value is closely related to the activeness of the photosynthetic apparatus. The experiments conducted showed that in the system of interaction between the soil, the plant and the effective layer of the atmosphere all analysed diffuse reflection indices changed with the emergence of water deficit. The index of photosynthetic apparatus capacity (ChlRI) is less susceptible to short-term soil drought than the indices of the efficiency of light use in the process of photosynthesis (R800, photochemical reflection index (PRImod) and flavonoid index (FRImod)) which change significantly, so that the degree of their change may be a reliable enough indicator of plant stress caused by water deficiency. It is advisable, however, when estimating and comparing the reaction of various plant cultivars, lines and new forms to the developed water deficiency, to include in the array of plants examined those cultivars whose optical properties and the range of their variation resulting from water deficit are known. This will ensure a more reliable ranking of analysed genotypes according to their drought resistance and will enhance the accuracy of the diagnosis.

The aim of the present work was to assess the physiological state of plants and photosynthetic apparatus activity in lettuce (Lactuca sativa L.) by non-invasive methods (leaf diffuse reflectance spectroscopy and chlorophyll fluorescence) under the deficiency of one of the macronutrients (nitrogen, phosphorus, or potassium). Our experiments assessed the deficiency of each of the macronutrients relative to plants vegetating under optimal nutrition. The used methods showed that the deficiency of macronutrients causes changes in the optical characteristics of lettuce plants (cvs. ‘Vitaminnyi’ and ‘Kokarda’), including a decrease in the chlorophyll content (57% and 51%) and a change in metabolism, which leads to a decrease in the efficiency of light energy conversion in photochemical processes of photosynthesis and an increase in the dissipation of excess light energy (19% and 10%). Linear regression equations, describing the relationship between net productivity and spectral characteristics of diffuse leaf reflectance with high accuracy, have been obtained. Changes in all studied indicators of the physiological state of plants under the influence of macronutrient deficiency are more pronounced at the early stages of development than in later periods, when the first symptoms of aging appear (decrease in ChlRI). The observed differences between lettuce cultivars and their response to nitrogen, phosphorus, or potassium deficiency are non-specific and mainly represent quantitative variation. The method for assessing the spectral characteristics of diffuse reflection of leaves seems to be the most promising for monitoring the physiological status of plants and early detection of nitrogen, phosphorus, or potassium deficiency.