Effect of free fall on higher plants
1Division of Biological and Medical Research, Argonne National Laboratory, Argonne, Ill., USA.
Life Sciences and Space Research
|January 1, 1973
Summary
Spaceflight
Area of Science:
- Plant biology
- Space biology
- Gravitational biology
Background:
- Understanding plant responses to microgravity is crucial for space exploration.
- Previous studies have explored effects on plant orientation, growth, and physiology.
Purpose of the Study:
- To summarize the influence of free fall on higher plants.
- To investigate potential effects on plant biochemistry, growth, and development.
- To analyze interactions between spaceflight conditions and radiation response.
Main Methods:
- Review of existing space-flight experiment data.
- Comparison of free fall effects with ground-based clinostat experiments.
- Analysis of plant physiological and developmental parameters.
Main Results:
- Free fall significantly impacts differential growth (tropism, epinasty) due to altered geostimulus.
- Ground-based clinostat experiments can mimic some free fall effects on differential growth.
- Observed enhanced microspore abortion and stamen hair stunting suggest a flight condition interaction with radiation response.
- A shift in cell cycle rhythm induced by free fall is proposed as the cause of observed interactions.
Conclusions:
- Short-duration spaceflights may not reveal broad biochemical or developmental changes.
- Differential growth responses in plants are sensitive to the absence of gravity.
- Free fall may alter plant cell cycle dynamics, influencing radiation sensitivity and development.
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