A Matter of Gravity—Understanding How Plants Grow in Space
by Tom Rickey (Environmental Molecular Sciences Laboratory/Phys.Org) Last month a rocket thundered off a NASA launch pad in Virginia, destined for the International Space Station. Nestled among the 7,400 lbs. of supplies was a handful of seeds designed to open new windows into our knowledge of how plants grow in space – information that could lead to growing fresh food in space for people aboard the space station or producing biofuel on our own planet.
Lewis (Norman Lewis, a Washington State University scientist) is working with researchers at EMSL, the Environmental Molecular Sciences Laboratory, a Department of Energy Office of Science User Facility at Pacific Northwest National Laboratory. EMSL scientist Mary Lipton will lead the analysis of thousands of the plants’ proteins to understand how the plants grown in space compare to counterparts grown in identical conditions – except for the force of gravity – back at Kennedy Space Center in Cape Canaveral, Fla.
The focus is on the lignin, the tough plant wall substance that allows plants to defy gravity and grow upright. Scientists will study how the plants respond to the weightless conditions of the space station. For instance, will the plants still grow “up” even in a microgravity environment?
But the material, a literal wall within a plant, is also a barrier to researchers at EMSL and elsewhere trying to create new plant-based biofuels. Lignin makes plants resistant to chemical manipulation, to transformation into plant-based biofuels. Thus the interest in exploring the behavior of plants deficient in lignin for Earth-based, everyday living.
“Plants greatly reduced in lignin can still live and grow, but they’re not really strong enough to thrive under most conditions. They can’t really stand up on their own – it’s like having fewer bones in your body to keep you structurally intact. But under the conditions of microgravity, the plants might do just fine with less lignin,” said Lewis, a Regents professor at WSU’s Institute of Biological Chemistry.
Viable plants with less lignin offer many things. On Earth, less lignin translates to easier methods to extract useful energy from the plant. In space, if the plant’s energy can be directed away from creating amorphous lignin, perhaps more of the plant could be eaten – more food for astronauts on long-range missions and maybe more oxygen produced for astronauts to breathe. This would also make space-grown plants easier to recycle. READ MORE