Growing cucumbers in space

New research growing cucumbers on ISS has found that the roots of these plants grew in the direction of water in weightlessness.

Plant roots grow to find water, according to a process known as hydrotropism. Roots are also influenced by gravity and tend to grow downwards, called gravitropism. To find out whether gravity or water had the greater influence on root growth, investigators grew cucumber plants in the microgravity environment on board the International Space Station. In their experiments, water (or hydrotropism) had more influence in controlling root growth.

“We will be able to utilize roots’ ability to sense moisture gradients for controlling root growth orientation and efficiently growing plants in future space farms,” said Dr. Hideyuki Takahashi, senior author of the New Phytologist study.

You can read the full science paper here.

This might sound obvious, but it isn’t. Past plant growth experiments on Mir and ISS had tended to show that plant roots did not know where to grow in weightlessness, suggesting that they needed gravity to guide the roots to water. Because of this, later experiments in space provided the roots complicated engineering to guide the roots to the water.

This experiment shows that maybe that complex engineering is not necessary, or at least could be simplified a bit. At a minimum it is crucial information engineers will need to design any future gardens for interplanetary spaceships with long term weightlessness.

A new harvest of vegetables in space!

A new harvest of vegetables in space!

Notice that this research is a partnership of the Russians and an American university. NASA is not included. When I wrote about this subject for Air & Space a few years ago, the American researcher explained that there was too much bureaucracy working with NASA. Moreover, the Russians were much more knowledgeable about crop research in space, as they had been doing it for decades already on their Salyut and Mir stations.

Russian greenhouse on ISS ungoes upgrade

The Russian greenhouse on ISS underwent an upgrade today.

The onboard greenhouse was dismantled in April last year, as a need arose to replace the outdated control unit, recalled head of the Rasteniya-2 (Plants-2) experiment, chief of the laboratory of the Institute of Medico-Biological Problems (IMBP) of the Russian Academy of Sciences (RAS) Vladimir Sychev. In early 2010, the crop area of the orbital garden was extended twice – the second leaf chamber was delivered to the ISS in which the crew managed to harvest the Mizuna lettuce, before the greenhouse was dismantled. Now, the cosmonauts will plant in these two chambers different cultures – super-dwarf wheat and dwarf tomatoes.

As I described in detail in Leaving Earth, the Russians have decades of experience in growing plants in space, with the goal of not only providing a natural system to recycle the station’s atmosphere, but also giving the astronauts a morale-boosting activity (gardening) that also gives them something tasty to eat. Though the engineering has still not made it possible to germinate seeds in weightlessness and then have grow there, this will be an absolute requirement if humans are ever to travel to the planets and beyond to the stars.