Growing Rice on Mars - Can science make it possible?

Monday - May 1 2023, 20:38 UTC - 1 year ago

Researchers from the University of Arkansas have managed to identify a strain of wild rice and two gene-edited cultivars that could potentially grow and survive in Mars-like soils. However, this still poses the huge challenge of Mars's thin CO2-rich atmosphere, cold temperatures, lack of sunlight and presence of toxic chemicals.

Mars is a barren, cold desert where no plant has ever sprouted from the planet's soil in its 4.5 billion-year history.

But science has taken this challenge head-on, as space agencies have been aiming to land the first humans on Mars in the coming decades. One barrier is that Martian soil contains perchlorate, a chemical that can be toxic to Earth plants.

Researchers from the University of Arkansas discovered that at least one strain of wild rice and two gene-edited cultivars may have the potential to grow in the harsh Martian soil. After extensive research, they identified a genetic mutation that modified for resilience against environmental stressors like drought and allowed the rice to grow and survive in Mars-like soils.

"We picked rice as it can persistently grow in a wide array of environments, but we are aware that its growth and ability to produce grains can be impacted by stress. We used these characteristics of rice as leverage to potentially grow an agricultural crop in Martian regolith simulant," Abhilash Ramachandran, a post-doctoral fellow at the Arkansas Center for Space and Planetary Sciences, told Interesting Engineering (IE) via email.

--- The Martian environment and soil conditions --- .

Before we get into the specifics of growing rice on Mars, let's take a look at the big picture of the red planet's current conditions.

Mars has become one of our solar system's most explored interplanetary destinations. This interest is due to its proximity and to the fact that billions of years ago, Mars may have had liquid oceans and a thick atmosphere and thus could have boasted a more hospitable environment — possibly even supporting microbial life. However, as time passed, the planet was transformed into the barren world we know today. The process by which Mars lost its atmosphere is still being studied. According to some studies, the loss of magnetic fields caused this drastic change, transforming Mars from a wetter and warmer world into a cold and dry planet.

Today Mars has a thin, carbon dioxide-rich atmosphere (about 95 percent CO2 and just 1 percent oxygen), making plant and human survival impossible. The temperatures are also bone-chilling, to put it mildly with temperatures as low as -225 degrees Fahrenheit (-153 degrees Celsius).

Because the planet is farther away from our star than the Earth, less sunlight falls on its surface. With the lack of magnetic fields, it is also vulnerable to lethal cosmic radiation.

Another barrier is the presence of toxic chemicals on the surface. Back in 2008, NASA’s Phoenix Mars lander spotted the widespread presence of the chemical perchlorate in soil, which can be harmful to growing plants. Additionally, Mars gets the name "red planet" from the abundance of iron minerals in its soil, which also pose a significant challenge to using the Martian soil for agriculture.

Although there is evidence of some nutrients in the Martian soil, the quantity required to grow plants is generally considered insufficient, and the nutrients present may be concentrated in a few locations. However, when Phoenix performed its first wet-chemical analysis, it did detect evidence of mineral nutrients important to plants, such as magnesium, sodium, potassium, and chloride.

Overall, this paints a bleak picture of groaning plants on Mars in the future — at least currently.