Induced abnormality in Mir- and Earth grown Super Dwarf wheat

Area of Science:

• Plant biology
• Space biology
• Astrobiology

Background:

• Wheat cultivation in space presents unique challenges for plant development.
• Previous studies indicated potential morphological and reproductive abnormalities in space-flown crops.

Purpose of the Study:

• To investigate the reproductive abnormalities of Super-dwarf wheat grown on the Mir space station.
• To identify potential causal factors for the observed reproductive failures in microgravity.

Main Methods:

• Comparative analysis of Super-dwarf wheat grown on the Mir space station (Svet Greenhouse) versus Earth-based controls.
• Microscopic examination of anthers and pollen from space-flown and Earth-grown plants.
• Controlled ground experiments exposing wheat to elevated ethylene levels.

Main Results:

• Space-grown wheat exhibited morphological and reproductive abnormalities, notably a complete absence of seed formation.
• While anthers appeared normal, pollen grains contained a single nucleus instead of the usual three, indicating non-viability.
• Ground experiments simulating high ethylene concentrations (1,200 ppb) replicated the reproductive abnormalities seen in space-flown wheat.

Conclusions:

• High ethylene levels in the space environment are a likely cause of reproductive failure in Super-dwarf wheat.
• Microgravity-induced stress may exacerbate ethylene's negative effects on wheat reproduction.
• Further research is needed to understand ethylene's specific role in plant reproductive processes in space.