Researchers at the University of Arkansas have created genetically modified rice plants that could potentially grow in the Martian regolith and become the first plants on the Red Planet.
Mark Watney, a character in the novel The Martian, grew potatoes in the Martian regolith to survive on the Red Planet. However, a group of interdisciplinary researchers from the University of Arkansas (USA) presented at the 54th Lunar and Planetary Science Conference report, according to which the first Earth plant on Mars could become genetically modified rice.
According to the university's official website, the Martian regolith is not suitable for terrestrial life forms in many respects. One of the most serious problems is the high concentration of perchlorates (up to one percent of the total mass of the regolith), salts that are toxic to plants. But if "normal" plants cannot grow, the only way out is to edit their genes.
The researchers modeled the Martian regolith using basalt soil from the Mojave Desert, then grew three varieties of rice on it: one control and two genetically modified. In the GM plants, the genome changes allowed them to better tolerate stresses such as drought or soil salinity. All three rice varieties were grown in "Martian" soil, conventional potting soil and their mixtures.
Alas, the pure "Martian" soil was not very suitable even for the modified plants, whereas when just a quarter of its volume was replaced with ordinary potting soil, the plants' condition improved markedly. Also, the researchers experimented with the content of perchlorate in the soil: according to their findings, three grams per kilogram - the threshold, insurmountable even for modified rice, but at three times lower concentration, which is observed in the Martian soil, GM-plants are able to survive.
In the future, scientists plan to determine how far perchlorates from the soil penetrate into plant organisms (this will find out if the "Martian" rice is suitable for food), and grow GM-plants in a special chamber that will simulate temperature and atmospheric conditions on the Martian surface. It is also possible that the results of the work will be useful not only for future colonists, but also for earthlings living in areas with high soil salinity, for example in Australia.
