Tolerance of LSS plant component to elevated temperatures

Area of Science:

• Agricultural Science
• Plant Physiology
• Environmental Science

Background:

• The stability of life support systems (LSS) relies on biological regeneration of resources, primarily driven by higher plants.
• Understanding plant tolerance to environmental stressors is crucial for maintaining LSS functionality.

Purpose of the Study:

• To evaluate the thermal tolerance of wheat and radish plant communities (cenoses) under varying temperature conditions.
• To determine critical temperature exposure thresholds and durations that cause irreversible damage to plant metabolic processes.

Main Methods:

• Assessing the thermal tolerance of uneven-aged wheat and radish populations.
• Monitoring photosynthetic processes, growth, and development under controlled temperature stress.
• Analyzing the kinetics of visible photosynthesis to identify reversible damage thresholds.

Main Results:

• Exposure to temperatures reaching 45°C for 20 hours caused up to 80% irreversible damage to photosynthetic processes, growth, and development in wheat and radish.
• The kinetics of visible photosynthesis can serve as an indicator for critical exposure times during thermal stress.
• Reversible metabolic damage occurs within specific critical exposure timeframes.

Conclusions:

• Elevated temperatures significantly impair plant photosynthetic efficiency and development, impacting LSS stability.
• Monitoring photosynthetic responses provides a method to establish safe operating limits for plants under thermal stress.
• Optimizing light intensity and air temperature can define admissible exposure periods, minimizing metabolic damage to plants in LSS.