A TIC-TOC Moment: Cotton Grows Better in Space than on Earth

By removing the masking effects of gravity, Gilroy’s team hoped TIC-TOC would reveal genetic clues that could lead to the production of resilient cotton plants that use resources more efficiently on Earth. On the space station, plant roots grow differently because they lack gravity as a directional cue to grow downward toward the water in the soil. Plus, there’s no gravity to pull water downward. 

The team explored how ordinary cotton grew in space compared with GM cotton to thrive under drought conditions. The modified and regular cotton grew better in space than the cotton in a control experiment back on Earth. The modified cotton grew the largest roots and experienced the least stress in spaceflight.

Genetic analysis of the unmodified cotton samples from space indicated these plants were more stressed out than their genetically modified counterparts. Ordinary cotton grown in space experienced increased protein degradation and showed various biochemical markers that signal stress not found in the genetically modified cotton.

The GM cotton grown in space also showed other changes in genes related to processes not observed before in regular cotton and generally not reported as spaceflight-related responses. Because both regular and modified cotton grew better in space, Gilroy says this must mean the growth effect is also directly related to the space environment and how they grew it. It’s possible, he said, that once the cotton-customised hardware mitigated the stressful effects of spaceflight, other features of microgravity may have encouraged the plants’ growth. Or maybe it’s something to do with cotton itself. By decoding why cotton grows better in space than on Earth, Gilroy’s team may be able to write a new chapter in farming, one that enhances our crops on the ground and in space.