Space surviving moss
The plant version of the tardigrade, or water bears, is the steppe screw-moss, Syntrichia caninervis. That are Chinese researchers writing in The Innovation.
Tardigrades are known about their ability to survive extreme circumstances. It can handle extreme cold, radiation and dehydration. It would therefore survive a trip in outer space. No researchers found a moss that could do this as well.
The moss, Syntrichia caninervis, is related to star moss. Syntrichia caninervis grows in deserts. There the moss is growing in extreme conditions, like cold, drough, and heat.
It was already known that the plant could still spring back to life after receiving water after being dehydrated for 98%. With the new study the researchers show that this is also the case after being kept for 3 to 5 years at -80 or 30 days at-196°C for a while. Even then, after defrosting, the moss kept steadily growing.
Syntrichia caninervis could survive space travel
Even gamma radiation did not appear to harm the moss. After receiving 500Gy, ten times the deadly dose for humans, it was even growing a little better than without radiation. Only by a radiation dose above 4000Gy did the plant show signs of stress.
Because on earth there are no environments in which all these extremes come together, did the researchers test if the moss could survive the environmental conditions on Mars. They exposed the plants to up to 7 days to simulated Mars conditions. Also in this case, afterwards under optimal earth conditions, the moss resumed its steady growth.
This all, so are the researchers suggesting, should make the plant ideal for growth on Mars. At the moment that appears to be a step to far. But it could opt for traveling through space together with the tardigrade.
Literature
Li X., Bai W., Yang Q., et al., (2024). The extremotolerant desert moss Syntrichia caninervis is a promising pioneer plant for colonizing extraterrestrial environments. The Innovation 5(4), 100657. https://doi.org/10.1016/j.xinn.2024.100657
Plant en Zo 