Experiments and appropriate facilities for plant physiology research in space

Light is a very essential parameter in a plant's life. Changing the quality and/or quantity of illumination will not only determine the further development (photomorphogenesis), but also effect spontaneous responses like curvatures (phototropism). But there are several still unknown links in the signal transduction chain from the perception of the light signals to the terminal response. It is known from ground-based experiments, that part of this signal transduction path is congruous with that of gravitational signals. Biosample is a technology development programme, which enables sophisticated experiments with whole plants in a microgravity environment. It allows complex sequences of gravitational- and light-stimuli with simultaneous recording of the plant's response (e.g. curvature of the stem) by video. This facility in union with new genetic mutants, which are less- or insensitive to light, gravity or both, are convenient tools for progress in plant physiology research.