Space-Grown Lettuce Faces Bacterial Risks in Microgravity

Photo byPhoto by Louis Hansel on Unsplash

Growing fresh greens in space for astronauts' health may seem like a great idea, but new research from the University of Delaware suggests it could pose risks due to increased susceptibility to bacteria. The study, conducted in simulated microgravity conditions, found that lettuce plants were more vulnerable to the Salmonella enterica pathogen in space-like environments.

The International Space Station (ISS) harbours aggressive bacteria and fungi, raising concerns about potential food safety outbreaks endangering astronauts' lives. Plant biologists emphasize preventing mission failures due to such outbreaks.

Using a clinostat device to simulate microgravity, researchers observed that lettuce plants exposed to S. enterica exhibited unexpected behaviour: the stomata pores, typically protective barriers, opened up, allowing bacterial invasion. Even beneficial bacteria failed to enhance plant defences, suggesting microgravity disrupts standard protective mechanisms.

Plant scientists highlight the unexpected response of plants to stress in microgravity, indicating a disruption in their ability to perceive gravity's orientation. While previous studies suggested space-grown lettuce was safe and nutritious, this research reveals potential challenges in warding off infections.

Considering the aggressive nature of space bacteria, the study underscores the need for further research to ensure food safety beyond Earth's orbit. Genetic modifications are proposed as one approach to mitigate risks associated with space agriculture.

University of Delaware microbiologists stress the importance of understanding bacterial reactions to microgravity to develop effective mitigation strategies, emphasizing the need to reduce risks for current and future ISS inhabitants.