8.9 Future outlook and prospects
With the advancement of molecular techniques and cellular imaging technologies, many
of the key players involved in tropisms have been identified and localized within cells.
However, how all these elements integrate and orchestrate tropisms during plant develop-
ment is far from understood. Microgravity experiments have only begun to clarify the sen-
sitivity of plants to gravity and light. It is likely that different species may be more sensi-
tive to particular environmental stimuli, resulting in an enhanced tropistic response. Future
long-term experiments that will use space stations as microgravity laboratories to study
tropisms are likely to reveal new information about how plants have evolved in a 1genvi-
ronment on Earth and to identify new tropistic responses that are masked by gravity. In ad-
dition to increasing basic knowledge, this information, in the long term, will aid in the de-
velopment of plants for use in bioregenerative life support systems during space missions.
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