A novel phototropic response to red light is revealed in microgravity
Article first published online: 8 MAR 2010
© The Authors (2010). Journal compilation © New Phytologist Trust (2010)
Volume 186, Issue 3, pages 648–656, May 2010
How to Cite
Millar, K. D. L., Kumar, P., Correll, M. J., Mullen, J. L., Hangarter, R. P., Edelmann, R. E. and Kiss, J. Z. (2010), A novel phototropic response to red light is revealed in microgravity. New Phytologist, 186: 648–656. doi: 10.1111/j.1469-8137.2010.03211.x
- Issue published online: 13 APR 2010
- Article first published online: 8 MAR 2010
- Received: 25 November 2009, Accepted: 31 December 2009
- Arabidopsis thaliana;
- European Modular Cultivation System (EMCS);
- International Space Station (ISS);
- red light;
- space biology
- •The aim of this study was to investigate phototropism in plants grown in microgravity conditions without the complications of a 1-g environment. Experiments performed on the International Space Station (ISS) were used to explore the mechanisms of both blue-light- and red-light-induced phototropism in plants.
- •This project utilized the European Modular Cultivation System (EMCS), which has environmental controls for plant growth as well as centrifuges for gravity treatments used as a 1-g control. Images captured from video tapes were used to analyze the growth, development, and curvature of Arabidopsis thaliana plants that developed from seed in space.
- •A novel positive phototropic response to red light was observed in hypocotyls of seedlings that developed in microgravity. This response was not apparent in seedlings grown on Earth or in the 1-g control during the space flight. In addition, blue-light-based phototropism had a greater response in microgravity compared with the 1-g control.
- •Although flowering plants are generally thought to lack red light phototropism, our data suggest that at least some flowering plants may have retained a red light sensory system for phototropism. Thus, this discovery may have important implications for understanding the evolution of light sensory systems in plants.