Perspectives for plant biology in Space and analogue environments

International audienceAdvancements in plant Space biology are required for the realization of long-duration exploratoryclass manned missions, where the re-supply of resources from Earth is not feasible for technical and economic constraints. Plants are key organisms in Bioregenerative Life Support Systems (BLSS) for the regeneration of resources (i.e. oxygen production through photosynthesis, water recovery by transpiration, and wastes recycling) and the production of fresh healthy food. Moreover, plants play a role in psychological support for astronauts. The definition of cultivation requirements for the design, realization and successful operation of BLSS must take into account the effects of Space factors on plant growth, development and reproduction. Altered gravitational fields and radiation exposure are the main Space factors inducing changes in gene expression, cell proliferation and differentiation, signaling and physiological processes, with consequences on tissue organization and organogenesis, thus on the whole organisms functioning. In this paper, the main findings of gravityand radiation-related research of the last years are summarized, highlighting the knowledge gaps that is still necessary to fill. A focus on existing facilities as well as requirements for future facilities to achieve fundamental biology goals is reported. Possible future experiments in the short-mediumlong term are proposed to achieve the targets of crewed Space exploration