Abstract
Columella (i.e., putative graviperceptive) cells of Zea mays seedlings grown in the microgravity of outer space allocate significantly less volume to putative statoliths (amyloplasts) than do columella cells of Earth-grown seedlings. Amyloplasts of flight-grown seedlings are significantly smaller than those of ground controls, as is the average volume of individual starch grains. Similarly, the relative volume of starch in amyloplasts in columella cells of flight-grown seedlings is significantly less than that of Earth-grown seedlings. Microgravity does not significantly alter the volume of columella cells, the average number of amyloplasts per columella cell, or the number of starch grains per amyloplast. These results are discussed relative to the influence of gravity on cellular and organellar structure.
Full text
PDF

Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- Hinchman R. R., Gordon S. A. Amyloplast Size and Number in Gravity-compensated Oat Seedlings. Plant Physiol. 1974 Mar;53(3):398–401. doi: 10.1104/pp.53.3.398. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Moore R. Calcium movement, graviresponsiveness and the structure of columella cells and columella tissues in roots of Allium cepa L. Ann Bot. 1985;56:173–187. doi: 10.1093/oxfordjournals.aob.a087001. [DOI] [PubMed] [Google Scholar]
- Moore R., Evans M. L. How roots perceive and respond to gravity. Am J Bot. 1986 Apr;73(4):574–587. [PubMed] [Google Scholar]
- Sack F. D., Suyemoto M. M., Leopold A. C. Amyloplast sedimentation kinetics in gravistimulated maize roots. Planta. 1985;165:295–300. [PubMed] [Google Scholar]
