A team of researchers from the University of Iowa has discovered that it is possible to successfully grow alfalfa on Mars. An article describing the work was published on the PLOS ONE website.

As scientists around the world reflect not only on the possibility of sending people to Mars, but also on the construction of shelters on the Red Planet, work continues on ways to make such projects possible. Before these dreams become reality, there are many challenges to overcome, including how to feed people living so far away. One option is to grow food inside protected enclosures. The buildings should simulate terrestrial conditions, since the plants that will be grown there will obviously be imported from Earth.

Growing plants on Mars will require several basic elements - soil, water, food and sunlight. In this new study, scientists have paid attention to the first two points. Mars doesn't have much to offer in terms of soil, but it does have basalt, a kind of volcanic rock. There are few substances in basalt that could be used by plants as food, and it is stony, not clay. Thus, for growing food, it will be necessary not only to change the basalt, but also to use plants that can grow in such conditions.

The researchers tried to grow several types of agricultural plants in finely ground basalt found on Earth. They found out that plants such as turnips, lettuce and radishes grow poorly in basalt. On the other hand, scientists have noticed that alfalfa copes very well. The researchers also found that if they grew alfalfa in basalt, and then planted other crops in the same soil, then these crops grew much better. For example, the yield of turnips increased by 311%.

Then scientists turned their attention to water, which is very scarce on Mars. It is mostly found in the ice at the poles. The water there is also very salty and therefore cannot be used for growing plants. To reduce the salinity of water samples on Earth, scientists have added bacteria known as Synechococcus, which can desalinate water. Testing has shown that Synechococcus can significantly reduce the concentration of salt, but the water will still be too salty for plants. Then the researchers filtered the water sample by pouring it through piles of basalt rocks, and obtained fresh water that can be used for growing plants.

A source: AstroNews