Studies on the growth and indole-3-acetic acid and abscisic acid content of Zea mays seedlings grown in microgravity

• Published in: Plant physiology (Bethesda) Vol. 100; no. 2; pp. 692 - 698
• Main Authors: Schulze, A., Jensen, P. J., Desrosiers, M., Buta, J. G., Bandurski, R. S.
• Format: Journal Article
• Language: English
• Published: Kennedy Space Center American Society of Plant Physiologists 01.10.1992
• Subjects: aba; Abscisic Acid - analysis; acide abscissique; acide indolacetique; acido abscisico; acido indolacetico; apesanteur; Canisters; contenido de materia seca; crecimiento; croissance; dry matter content; Environmental and Stress Physiology; Ethanol; Gibberellins - analysis; Gravity; growth; iaa; Indoleacetic Acids - analysis; ingravidez; Life Sciences (General); Microgravity; Organ Size; Plant growth; Plant Growth Regulators - analysis; Plant roots; Plants; plantulas; plantule; Seedlings; Space Flight; Space life sciences; teneur en matiere seche; Vehicular flight; Weightlessness; zea mays; Zea mays - chemistry; Zea mays - growth & development; zero gravity; Nasa Program Space Biology; Nasa Discipline Plant Biology; Nasa Discipline Number 00-00; Nasa Discipline Number 40-50; Non-Nasa Center; Sts-34 Shuttle Project; Manned; Short Duration; Nasa Program Flight; Flight Experiment; NASA Discipline Number 00-00; NASA Program Space Biology; NASA Program Flight; NASA Discipline Number 40-50; NASA Discipline Plant Biology; Non-NASA Center
• ISSN: 0032-0889; 1532-2548
• DOI: 10.1104/pp.100.2.692

Measurements were made of the fresh weight, dry weight, dry weight-fresh weight ratio, free and conjugated indole-3-acetic acid, and free and conjugated abscisic acid in seedlings of Zea mays grown in darkness in microgravity and on earth. Imbibition of the dry kernels was for 17 h prior to launch. Growth was for 5 d at ambient orbiter temperature and at a chronic accelerational force of the order of 3 X 10(-5) times earth gravity. Weights and hormone content of the microgravity seedlings were, with minor exceptions, not statistically different from seedlings grown in normal gravity. The tissues of the shuttle-grown plants appeared normal and the seedlings differed only in the lack of orientation of roots and shoots. These findings, based upon 5 d of growth in microgravity, cannot be extrapolated to growth in microgravity for weeks, months, and years, as might occur on a space station. Nonetheless, it is encouraging, for prospects of bioregeneration of the atmosphere and food production in a space station, that no pronounced differences in the parameters measured were apparent during the 5 d of plant seedling growth in microgravity.