PLANT CULTIVATION IN SPACE: NEXT STEPS TOWARDS THE SVET-3 SPACE GREENHOUSE PROJECT AND CURRENT ADVANCES

摘要

This paper presents the next steps in the development of an advanced SVET-3 Space Greenhouse. This includes wider parameter monitoring and adaptive control of the shoot and root environment so as to provide the most favorable conditions for plant growth and development. A new system for precise plant shoot zone environment monitoring was added to the existing SVET-2 SG equipment (using the ME-4610 data acquisition system). Some main sensors' sub-systems for measurement of light intensity, air humidity, temperature, air pressure and airflow velocity are developed and described. Laboratory verification tests of these systems in two experiments with different lettuce plants variety and chamber volume were carried out. Ground research was performed to study the processes involved in the root zone medium in earth and model microgravity conditions and on this basis to make some optimizations for providing an adequate root environment in space. Biotechnical experiments were carried out to investigate the plant response to artificial hypo-oxygen and waterlogging "stresses" in substrate Balkanine. The results obtained showed that even a small rise of moisture in the substrate, when saturation had occurred in the bottom layers, can lead to oxygen deficiency in the plant root area and to photosynthesis reduction as a result.