A tiny flowering plant called Arabidopsis thaliana is heading into a close encounter with powdery mildew aboard the International Space Station. The University of Florida experiment will test whether microgravity changes how the fungus infects plants—and whether plants defend themselves differently in space.
The question matters for future missions to the moon and Mars. Crews on long journeys may grow fruits and vegetables in bioregenerative life support systems: habitats that use plants and other living processes to help provide food and renew resources such as oxygen and water. Growing food on site could reduce the need to send supplies from Earth. But those systems will only help if crops stay healthy. As University of Florida researcher Andrew C. Schuerger put it, “Wherever plants and humans go, plant pathogens are soon to follow.”
The investigation, named MVP-Plant-02, launched to the station on Oct. 13. It is led by University of Florida Institute of Food and Agricultural Sciences researchers Andrew C. Schuerger, Robert Ferl and Anna-Lisa Paul. The team will study Arabidopsis, a small plant related to mustard, and Golovinomyces cichoracearum, the fungus that causes powdery mildew.
Researchers will track whether the fungus grows more aggressively in microgravity and how the plant’s gene activity changes as the disease develops. Comparing infection and gene activity may help reveal how plants respond to disease when gravity is very low. That knowledge could guide efforts to keep crops productive during extended space missions.
The experiment uses the Multi-Use Variable-g Platform, or MVP, developed by Redwire Space Technologies Inc. It allows tests aboard the station under different gravity conditions. The team will compare plants grown in microgravity with plants kept at Earth-like gravity on the station, and with a separate ground control at Kennedy Space Center. The comparisons can help separate the effects of microgravity from other conditions involved in growing plants in space.
A key difference from earlier space-based plant disease research is when infection begins. The team will grow the plants from seeds in space and apply the fungal spores only after the plants have experienced microgravity. In previous research, plants were infected before launch. Starting the infection in orbit lets scientists examine how microgravity may shape plant defenses before the fungus arrives.
To do that, the University of Florida and Redwire team created the Conidia Application Device. It is designed to apply fungal spores to plant leaves in a closed system, with sterile ejections during spaceflight. Kylee Soltez, a University of Florida master’s graduate on the science team, said the team developed the first plant pathogen inoculation device for use in spaceflight.
The results will not solve every challenge of growing food beyond Earth, but they can provide a clearer picture of how disease behaves in space. By learning when plants are most vulnerable and how infection unfolds, researchers can help make future space gardens more dependable—so crews traveling far from Earth have a better chance of growing fresh food along the way.