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The proposed system of automated nutrient solution preparation for plant cultivation in microgravity consists of an ion-exchange fabric artificial soil (AS) as a root-inhabited medium, a pack with slow release fertilizer as the main source of nitrogen, phosphorus and potassium and a cartridge with a granular mineral-rich ionite as a source of calcium, magnesium, sulphur and iron. Experiments proved that fabric AS BIONA-V3 is capable to stabilize pH of the substrate solution within the range of 6.0 to 6.6 favorable to the majority of vegetable cultures. The experimental data attested suitability of this technique of water forcing through mineral-containing packs to automate nutrient solution preparation for crops cultivated in space greenhouses, and to minimize the stock of fabric AS onboard the space vehicle.

The paper presents ideas of optimizing the mineral nutrition system for salad crops in a space greenhouse. Experiments showed that to use mineral-saturated fiber ionite BIONA-V3 as an artificial soil will require to upmass a lot of expandable materials because of low specific content of nutrients. An additionally mineralized fiber soil makes possible to reduce mass of ionite in 5.6 times and volume in 28 times. The proposed mineral supply system is composed of two enrichment catridges with granulated ionite BIONA-V3 and slow-releasing fertilizer Osmocote 114-14-4, and a controller of irrigation water electric conduction stabilizer. Tests showed that this system provides sufficient mineral nutrition to plants and can be recommended for in-flight testing.

The article describes the telemedicine complex (TM) for real-time medical informatics communication and interaction between medical personnel at the spacecrew landing site and in the mission control center. Scenarios of TM complex employment for crew examination after Standard landing, in bad weather or for providing care to cosmonauts with unsteady or unsatisfactory health state after ballistic landing are outlined. Basic requirements to the TM-assisted express diagnostics of returned spacecrew are defined.

The salad machine experiment was aimed to fulfill performance testing of a prototype of space conveyor-type cylindrical greenhouse PHYTOCYCLE-SL, to study growth and development of plants, and to evaluate microbial contamination of equipment in the closed manned environment. Crops of leaf cabbage Brassica chinensis L., cultivar Vesnianka were raised in the time interval between MARS-500 days 417 and 515. The greenhouse proved it serviceability demanding 17 min/(man x d) in the normal mode. Most likely that the slow growth rate and deviations in plant morphology were caused by the presence of volatile pollutants in the greenhouse compartment Accumulation of micromycetes was observed at the sites of humid surfaces contact with ambient air; reduction of the artificial soil area contacting with air decreased population of micromycetes in 40 times. Cabbage leafs were free of pathogenic microflora. These results of the experiment helped develop recommendations on how to work out some units and systems in projectable greenhouse VITACYCLE-T

The vegetable cultivation technology developed in view of long-term autonomous missions is based on root nutrition provided by fiber artificial soils (AS) containing ion-exchange resins. Useful life of ASs is limited by two factors which are nutrients depletion in ion-exchanger and clogging of the AS threshold space by roots remnants. Purpose of the investigation is to try out hydrolysis and ensuing microbial decomposition of roots remnants as a way to extend the resource of used fiber ionite AS. This principle of doing away with the roots remnants recovers almost completely the maximal water-absorbing capacity of AS BIONA-V3 so that it can be used again for crops cultivation.

Stability of Chinese cabbage crop colonization by methanolic bacteria Methylovorus mays, Methylomonas methanica and Methylosinus trichosporium inoculated using a space-applicable method was evaluated. Besides, trends of methane and methanol concentrations in the pressurized chamber with inoculated and uninoculated crops were calculated. Methylovorus mays and Methylosinus trichosporium were shown to establish more stable colonization as compared to Methylomonas methanica. Also, stable association of methanolic bacteria with plants reduced airborne methanol 75% faster owing to its uptake by bacteria. Therefore, inoculation of these microorganisms can be viewed as a promising method of controlling volatile pollutants in space vehicle atmosphere. Methane drop after 6-hour exposure to inoculated control and test crops was not significant.

The authors substantiate the choice of a mobile telemedicine facility (MTLF) configuration for elimination of medicosanitary consequences of emergency situations fit in minibus Sobol. The global competitiveness criterion has been adapted to consider the MTLF cost-quality gain/reduction ratio in comparison with the basic model. This approach permitted determination of the vector of MTLF attributes, indices of user (doctor) satisfaction, and coefficients of significance for each MTLF vector component. The proposed competitiveness criterion and calculation procedure can be applied in optimization of the structure and composition of MTLF and other intricate telemedicine systems.

IBMP has developed a technology and unit for cultivating self-opening crops on a convex planting surface illuminated by light-emitting diodes mounted on an external concentric panel ("Hemisphere"). The unit has a structure of two-member clinostat with semispherical plant growth chamber with a 600-mm diameter and a speed of from 1 to 10 revo about each axis; water potential in the root supply system is maintained at 1.0 +/- 0.45 KPa. Having the data of 1200 measurements in the growth chamber, PAR latitude and meridian gradients were determined which did not exceed 0.7 micromol/(m2 x s x cm) in the work area and differed from the radial gradient by order and, therefore, had a negligible contribution to the axial organs' deviation from the radial directions during laboratory tests. Maximal centrifugal acceleration was equal to 10(-10) of the acceleration of gravity and did not impact the gravitropic crop reactions in the growth chamber. Five 5-day tests with semidwarf wheat Triticum aestivum L., cult. Lada were performed in the "Hemisphere" growth chamber turned at different angles relative to the gravity vector. In immobile growth chamber plants inclination from the vertical was a function of the angle between the PAR gradient and vector and the gravity vector at the site of each seed. Crop rotation at 3 revo about the horizontal axis did not produce noteworthy plant inclination suggesting neutralization of the plant geotropic reactions. In all tests about 80% of the plants formed the first leaf and about 20% reached the coleoptiles phase. Morphometric differences in the tests were insignificant. On a balance, the tests showed that prototype of space greenhouse "Hemisphere" is fit to run laboratory investigations of the plant gravitropic reactions in both static and dynamic conditions.

Installation of a greens production system on the International space station will mean a leap toward biological regeneration of food in long-duration space mission. Today, priority is given to green cultures as supplements of space rations and a psychological support to crews in exploration missions to Mars, and also as least resource-intensive. Cylindrical salad greenhouse "Phytoconveyor" designed at the Institute for Biomedical Problems is highly productive, energy-efficient, and requires minimum of crew time for. Dimensions of the greenhouse are 540 x 590 x 400 mm, power demand is 0.25 kW, and the Plant chamber volume is about 0.09 m3. 'Phytoconveyor" has a planting unit with six cylindrical root modules. The total illuminated crop area is about 0.4 m2. The lighting unit consists of red (660 nm) and blue (470 nm) light-emitting diodes on the inner surface of a spiral cylinder coaxial with the roots module unit that generate the photon flux density 350 micromol x M(-2) x s(-1) at a distance of 4 cm. Each root module has a porous tube wrapped up in a fiber substrate with ion-exchange resins and is covered with a lightproof plastic with seed slits. The "Phytoconveyor" design includes a programmable reverse watering system. Given the 24-hr light period, the laboratory model of "Phytoconveyor" can produce up to 300 gram of fresh greens every 4-5 days. The greenhouse was designed with due account of resource limitations on the ISS Russian orbital segment.

Growth and development of Fusarium oxysporum intact strain and strains subjected to irradiation by low gamma-neutron doses were studied during cultivation on intact substrate and substrate irradiated by a gamma-source at 29 microGy. There was a striking difference in growth and sporification between the strains cultivated on irradiated and intact substrates. Irradiated Fusarium oxysporum strains exhibited manifest antagonism to one another and the non-irradiated strain. Electroconductivity of substrate after gamma-irradiation at low doses was noted to slow down markedly. The authors come to the conclusion that nutrient molecules may become more available to micromycets because of alteration of proton activity in consequence of preliminary irradiation.

The effects of chronic exposure in the combination of low-dose gamma- and neutron radiation on growth of Brassica pekinensis (lour) Rupr, var. Khibinskaya, and micromycetes of Fusarium oxysporum, a representative of soil microflora were stadied. Seeds, water and vegetating plants raised from previously irradiated seeds were subjected to radiation exposure. The gamma-neutron dose rate was -0.013 sGy/d and the neutron flux was -20 n/cm2 d. Growth of Brassica pekinensis and of Fusarium oxysporum on the background of weak chronic ionizing irradiation by radioactive nuclides was noticeably changed when compared with the growth in the normal radiation environment. The radiosensitivity of Fusarium oxysporum isolated from the artificial soil following 60-d exposure was far higher than the radioactivity of the culture isolated from non-irradiated soil. Fusarium oxysporum isolated from the irradiated soil failed to form spores normally even when cultivated in a non-irradiated nutrient substrate without further exposure. These peculiarities persisted at least for four months. 15-mo gamma- and neutron exposure of Brassica pekinensis seeds held in storage for 5 years retained their original germinating capacity, whereas the non-irradiated seeds suffered deprivation of this quality. It was noticed that the Brassica pekinensis reaction on chronic exposure of low doses was markedly dependent on the growth conditions non-related directly with the radiation background.

The laboratory model of space production salad conveyer PHYTOCYCLE SD utilizes the principle of self-opening of plants growing under the light-emitting diodes. A computer model has been proposed to estimate greenhouse productivity as a function of design values. The model was used to compare greenhouses with a cylinder and flat crop surface. Self-opening crops on the cylindrical surface were shown to have a 30% advantage in production per a unit of light energy. Based on the analysis of the dependence of specific productivity on light intensity, the most effective light level is 300-350 micromol x m(-2)s(-1). It was established that PHYTOCYCLE SD productivity per a unit of orbital resources is much better compared with the known research plant growth facilities and can meet the vitamin (A and C) and rough dietary fibers' demand of three crew members.

Wheat plants Triticum aestivum L., Apogee cultivar, were grown in the natural and inverse orientation of the Earth gravitational field. Special vegetation containers with double bottom were used for the cultivation. The upper bottom made of porous titanium served as a hydrophilic porous membrane stabilizing aquatic potential in the root-inhabited zone at a given level. Normal plants yielding viable seeds were obtained for both natural and inverse orientation. In our experiments, the inverse orientation induced dry weight accumulation by the plants as well as development of productive tillering shoots and increased the shoot-root dry weight ratio.

In order to evaluate the effects of gravity on growing plants, we conducted ground-based long-term experiments with dwarf wheat (cultivar "Apogee USU") and Chinese cabbage (cultivar "Khibinskaja"). The test crop had been grown in overhead position with HPS lamp below the root module so that gravity and light gradients were in opposite direction. Plants of the control crop grew in normal position under the same lamp. Both crops were grown on porous metallic membranes with stable--1 kPa water potential on the surface. Results from these studies allowed us to examine the significant differences in growth and development of the plants as well as the root systems in relation to the gravity force. Nevertheless, the experiments in greenhouse Svet aboard the Mir space station proved that it is possible to compensate the effects of weightlessness on higher plants by manipulating gradients of environmental parameters (i.e. photon flux, water potential in the root zone, etc.). Even in ground studies Svet productivity averaged no more than 14 gm of fresh salad biomass per a day. This does not provide a sufficient supplement nutrients to the ISS crew. A cylindrical design of a space plant growth facility (SPGF) allows for maximal productivity under very tight energy and volume limitations onboard the ISS and a number of operational advantages.

To improve reliability of plant's moistening and aeration control in microgravity, an original root supply system with a periodic return water flow has been designed and tested in laboratory. For 30 days crops of Pekinese cabbage (Brassica pekinesis (Lour Rupr), Khibini sort) were raised in the test bench which allowed adjustment of water potential in the root zone within a preset range. A three-step water potential control algorithm included water injection with a pump-dispenser, a pause, and water sucking back to a desired value of water potential. The following parameters of the control cycle were selected in a series of two experiments: time of water injection (2.5 hr) and return (1.5 hr), and a pause of 8 and 20 hr, respectively. Magnitude of water potential about the root module axis was controlled in the range from -1.3 kPa to -3.0 kPa in both experiments and maintained at -1.3 kPa in the control. The root modules consisted of porous metaloceramic tubes wrapped in fibrous ion exchanging cloth and a light-proof film with planting slots on top. In the first experiment, plant characteristics were comparable to the control. The developed procedure and technology can be used to provide favourable moisture-air conditions in the root zone. By and large, the system of root nutrition with a periodic water return has demonstrated high capacity during the ground-based cultivation of plants. To use this system in space greenhouse, it is necessary to specify operational parameters for the microgravity environment.

To decide on the light status of plants in space greenhouse, a theoretical study was undertaken to correlate specific productivity of space greenhouse with illumination characteristics including vertical PAR flux density (I), photoperiod (tau), and crop leaf index (L). It was demonstrated that in pace with I the daily productivity per a volume unit tended to monotonously approach maximum at I = Ip, whereas the greenhouse energy efficiency ME peaked at I = IE, IK < IE < IP, where IK is a compensation point of the light curve of crop photosynthesis. Proposed are compromise criteria to optimize illumination as a maximum of linear combination of MV and ME and coefficients which account for the cost of a space station volume unit and a unit of board power supply, and as maximum of product Q = MV.ME. Experimental results serve as the basis for a technique for determination of the best, by the Q criterion, light status parameters for three types of space greenhouses: research growth chamber for synchronous cultivation of leaf mustard, wheat growth chamber with fixed crop density, and green conveyer for cultivation of Brassica pekinensis (Lour Rupor). For the last mentioned Q effective I and tau values differed with the conveyer step. The technique allows design of ground-based experiments aimed at determination of the most effective light status of space-grown crops.

Wheat crop was grown in various root modules (RM) in which nutritional solution was injected through porous membrane (2-6 microns). Seeds were laid on the surface of membrane or in pearlite covering the membrane. Root modules 1 and 3 contained ceramic porous tubes 10 mm and 22 mm in diameter, respectively. RM 2 was outfitted with a porous titanium plate, RM 4--with a porous ceramic tube (Ø 10 mm) buried in pearlite, and RM 5--with a porous titanium plate under the 2.5 cm thick layer of pearlite. The area of membrane surface per one plant was equal to 3 cm2 in RM 1 and about 17 cm2 RM 2 and 3. Pearlite volume per a plant made up about 40 cm2 in RM 4.5. The object of study was Triticum aestivum L., sp. Super Dwarf. The plants grew for 49 days under the white light of luminescent lamps at water potential (WP) = -0.4, -3.0 and -5.0 kPa. WP of pearlite equal, dry mass and anticipated productivity of the crop were much higher as compared to RM without pearlite. Significant reduction of these parameters was reflective of WP drop no matter the RM type. However, it was more expressed at -5 kPa. In RM filled with pearlite the mass and productivity of crop reduced at -5.0 kPa. Design of RM essentially altered the volumetric spread of roots. Thus, root math was formed immediately on flat porous plates, commonly below the bare tubes and both on top and on the bottom of RM with pearlite. These data can help development of RM for space greenhouses.

In ground-based experiments reproducing conditions in experiments in the Mir greenhouse Svet super dwarf wheat was raised at water potential (WP) in root modules with pearlite within the range from -0.5 kPa to -3.0 kPa. At -2.0 kPa the number of florets in spikes, mainly the tiller ones, was considerably reduced and the actual spikes were fully barren. With WP equal to 0.5 kPa and -1.0 kPa, the grain component in the mass of a completely ripe shoot made up 46% and only 32% with WP at -2.0 kPa. With WP = 3.0 kPa, spikes of the main shoot and tillers were fully barren. In the WP range from 0.5 kPa to 1.0 kPa plants developed two tillers and no more than one tiller at 3.0 kPa. In the experiment with elevated air temperature mass of tillers at 1.0 kPa was by 39% lower as compared to the data from the experiment at the normal temperature. Degenerated anthers and abnormal pollen grains were again the cause of full barrenness of spikes grown at the normal temperature.

In a set of 8 experiments, in leaf mustard Brassica junceae L. (cult. Volnushka) and in soft wheat Triticum aestivum L. (cult. Super Dwarf) there has been studied dynamics of accumulating biomass in the ontogenesis in accordance with the value of water potential in the root-habitable medium. Besides, in wheat there has been investigated the process of forming the grain crop capacity in a period between V and XII stages of the organogenesis from Kuperman's classification. The plants have been grown in the root modules with the perlite used as a substitute for soil and with water supply through the porous hydrophilic membranes. The levels of water potential in the root-habitable medium, namely in the perlite, were kept unchanged in the range from -0.5 to -13 kPa (or from -5 to -130 cm water column) which corresponded to volumetric humidity ranged from 63 to 25%. Tests exposition was in the range of 13 to 78 and 25 to 46 days for wheat and mustard, respectively. The value of upper limit of an allowable water potential was determined from the magnitude of critical pressure of the puncture at which the most large through pores in the perlite layer break free of water, the value of lower limit was determined after criterion of a significant decrease in the plants harvest. In accordance with the paper results an allowable range of water potential in a perlite-based root-habitable medium ranged from -1.0 to -2.0 kPa which was in agreement with the range of volume humidity from 61% to 51%. In decreasing the water potential beyond the lower limit of mentioned range to -3.0 kPa, the mass of mustard shoots has reduced by 30% and the wheat crop was not good. The elaborated procedure and equipment can be used for determining the thresholds of permissible water potentials (humidity) for any soil substitutes irrespective of the construction of root module and the species of cultivated plants.

The analysis of the study associated with cultivating the leaf cabbage, small radish in the Russian-Bulgarian greenhouse "Svet" aboard Mir orbital space station in 1990 has demonstrated that under microgravity conditions the zeolite substrate "Balkanin" with particles dimensions of 1-3 mm placed in the root modules of the greenhouse "Svet" did not ensure the sufficient transfer of the water from moisture-saturated wicks to the periphery of the vegetation vessels what is attributable to the peculiarities of hydrophysical characteristics of the substrate used. There presented the results of experimental research on the hydrophysical and agrochemical characteristics of the ion-exchange substrates of two other types--"Biona 312" and "Biona V" prepared on the basis of the artificial ion-exchange resins: cationite--CU-2 and anionite EDE-10P. For these substrates there found the estimates of humidity correlating with the loss of gassy pores as well as there measured the specific weight of the solid phase and the volumetric weight. There presented data on the content of the nutrients as well as the results of assessing the biological productivity potential of the tested substrates in the "Svet" greenhouse root modules. The characteristics obtained are indicative of the possibility to use the mentioned substrates in space greenhouse of the "Svet" type.

The laws of light distribution in plants sown on the flat plane, spherical or cylindrical surfaces were investigated. In mhicrogravity where the plants are arranged radially the level of illumination of lower leaf strata is higher on curvilinear than on flat surfaces. This is due to the following: as the plants grow they get separated; also, the concentration of the light flux increases with depth of plants on the curvilinear surfaces. In view of this, a space green-house is suggested, the design of which provides high productivity per unit volume and per unit energy of the incident flux of photosynthetically active radiation.

The threshold of the phytotoxic effect (PTE) of ammonia at a concentration of 10 to 20 mg/m3 on 28-day lettuce plants was evaluated during a single 2-hour exposure. The rate of Hill's reaction, level of energization of chloroplast membranes during leaf illumination as well as visible photosynthesis of lettuce plants from the beginning of fumigation to vegetation day 31 were recorded. Similar changes in the above parameters induced by ammonia were seen. This suggests that photosynthesis was inhibited already at light stages. As a measure of PTE, 10 per cent decrease of the photosynthetic productivity of plants exposed to fumigation was recommended in comparison with controls during the vegetation period. According to this measure, the PTE of ammonia amounted to 20 mg/m3 in the above experimental conditions.