MadSci Network: Botany |
Plants respond to gravity, termed gravitropism, so it would be unusual to grow them upside down. If you turned a potted plant 180 degrees, the shoot tips would start to bend upward again within a few hours. Parts of the stem that have already become woody could not bend but growing shoots could. The upside down plant would probably survive if the leaves received sufficient light. Lateral roots often grow roughly horizontally so being upside down would not be as much of a problem for roots. You would have to water the upside down pot from the bottom somehow. This would be an interesting experiment. Scientists interested in growing plants in the space station and on space flights have sometimes used a pea plant, named ageotropum, that lacks the normal gravitropic response. The ageotropum pea roots do not respond to gravity at all while the shoots respond to gravity in the light but not in the dark. Reference Jaffe, M.J., Takahashi, H. and Biro, R.L. 1985. A pea mutant for the study of hydrotropism in roots. Science 230: 445-447.
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