Researchers peaked behind proverbial bedroom doors to get a real-time view of plant sex in microgravity. What they found might have implication for the future of space travel and could give insight into the effects of low gravity on human brains.
When pollen grains land on the female part of a flowering plant, the stigma, it beings to grow a pollen tube. These tubes are the fastest growing cells in the plant kingdom, and they were ideal for this study as they do change in response to gravity and rely on intercellular transport to grow.
The study, published in PLoS One, simulated microgravity in the lab using centrifuges and ESA's Random Positioning Machine. They used microscopy to watch the growth of pollen tubes in real-time. They found that tubes grown in microgravity were 8 percent smaller, while tubes grown in 5 times Earth gravity were 8 percent wider, and at 20 times Earth's gravity were 38 percent wider. Surface expansion rates of the tubes dropped 39 percent in microgravity conditions.
This study could influence how space agriculture is approached in the future. At the very least, it gives insight into how Earth plants might adapt to space conditions. Human brain function also relies on intercellular transport as well. The effects of microgravity on intercellular transport in neurons could have a role in cognitive difficulties humans experience in space.