If astronauts are to be able to travel deeper into space, they will have to start growing their own food. A topic which Wageningen UR is addressing in several ways. This year several projects have been started and the Horticulture and Product Physiology group is playing an important role there.
Farming on other planets poses huge challenges. Take Mars. The planet is continuously bombarded with harmful radiation, the atmosphere is extremely thin and it is bitterly cold. The temperature ranges between minus 143 and plus 35 degrees Celsius. So any growing of crops will have to be done in a closed environment, says Leo Marcelis, professor of Horticulture and Product Physiology. Then radiation, temperature and the lack of an atmosphere are less problematic. Moreover, it enables the colonists to use all kinds of techniques which were developed for terrestrial horticulture, such as the most efficient LED lighting.
Marcelis himself is doing research – in a European collaboration – on the effects of reduced gravity. Gravity on Mars is only one third as powerful as that on earth and that difference influences plants in several ways. Scientific research in space has already demonstrated that plants not only need gravity to grow in the right direction: the stems grow towards the source of light, and the roots towards water and nutrients. If there is no gravity and no clear single source of light, plants grow in all directions.
Besides the direction of growth, the plant is affected in other ways too. Marcelis wants to understand, for instance, how the flow of nutrients and water through the plant changes. For the time being he is only studying this on earth. He and postdoc Sander van Delden are going to grow plants in a 'centrifuge'. By adjusting the rotation speed, pressure is exerted on the plant that equals that of Martian gravity, for example. Of course this system does not get rid of the earth’s gravity, so eventually they want to do tests in space. ‘But you only get permission for research in the ISS,’ says Marcelis, ‘when it has been so well prepared that the chance of success is almost 100 percent.’ They will now first improve their growing system, so as to be able to take more precise measurements.
(source: Wageningen-UR Resource magazine nr. 19 - 4 June 2015)
This research is conducted as part of the EU-funded TIME SCALE project.