Gardening in Space with HydroTropi

Jan 19, 2011 By Jessica Nimon
HydroTropi in space
Cucumber roots grew laterally in space following 70 hours in microgravity on STS 95. Credit: JAXA

(PhysOrg.com) -- Plants are fundamental to life on Earth, converting light and carbon dioxide into food and oxygen. Plant growth may be an important part of human survival in exploring space, as well. Gardening in space has been part of the International Space Station from the beginning -- whether peas grown in the Lada greenhouse or experiments in the Biomass Production System. The space station offers unique opportunities to study plant growth and gravity, something that cannot be done on Earth.

The latest experiment that has putting their green thumbs to the test is Hydrotropism and Auxin-Inducible Gene expression in Roots Grown Under Microgravity Conditions, known as HydroTropi. Operations were conducted October 18-21, 2010, HydroTropi is a Japan Aerospace Exploration Agency (JAXA)-run study that looks at directional root growth. In microgravity, roots grow latterly or sideways, instead of up and down like they do under Earth’s gravitational forces.

Using cucumber plants (scientific name Cucumis sativus), investigators look to determine whether hydrotropic -- plant root orientation due to water—response can control the direction of root growth in microgravity. To perform the HydroTropi experiment, astronauts transport the cucumber seeds from Earth to the space station and then coax them into growth. The seeds, which reside in Hydrotropism chambers, undergo 18 hours of incubation in a Cell Biology Experiment Facility or CBEF. Then the crewmembers activate the seeds with water or a saturated salt solution, followed by a second application of water 4 to 5 hours later. The crew harvests the cucumber seedlings and preserves them using fixation tubes called Kenney Space Center Fixation Tubes or KFTs, which then store in one of the station MELFI freezers to await return to Earth.

The results from HydroTropi, which returns to Earth on STS-133, will help investigators to better understand how plants grow and develop at a molecular level. The experiment will demonstrate a plant’s ability to change growth direction in response to gravity (gravitropism) vs. directional growth in response to water (hydrotropism). By looking at the reaction of the plants to the stimuli and the resulting response of differential auxin -- the compound regulating the growth of plants -- investigators will learn about plants inducible gene expression. In space, investigators hope HydroTropi will show them how to control directional root growth by using the hydrotropism stimulus; this knowledge may also lead to significant advancements in agriculture production on Earth.

Explore further: New satellite sensor will analyze and predict severe space weather

More information: www.nasa.gov/mission_pages/station/research/experiments/HydroTropi.html

Related Stories

NASA to Study Seeds in Space to Understand Plant Growth

Feb 08, 2010

(PhysOrg.com) -- NASA scientists hope to better understand exactly how and why plants grow differently in space in an experiment named, Tropi. Future astronauts may be able to grow plants as part of life support systems on ...

Botanist Sends Plant Seeds to ISS

Jun 21, 2006

When the space shuttle Discovery launches July 1 it will carry the research of Miami University professor John Kiss to continue studying if we can grow food in microgravity.

Getting to the root of nutrient sensing

Jun 14, 2010

New research published by Cell Press in the June 15th issue of the journal Developmental Cell, reveals how plants modify their root architecture based on nutrient availability in the soil.

Circadian clock controls plant growth hormone

Aug 13, 2007

The plant growth hormone auxin is controlled by circadian rhythms within the plant, UC Davis researchers have found. The discovery explains how plants can time their growth to take advantage of resources such ...

Alternative Energy Crops in Space

Mar 10, 2010

(PhysOrg.com) -- What if space held the key to producing alternative energy crops on Earth? That's what researchers are hoping to find in a new experiment on the International Space Station.

Recommended for you

SpaceX launches supplies to space station (Update)

9 hours ago

The SpaceX company returned to orbit Friday, launching fresh supplies to the International Space Station after more than a month's delay and setting the stage for urgent spacewalking repairs.

Sun emits a mid-level solar flare

9 hours ago

The sun emitted a mid-level solar flare, peaking at 9:03 a.m. EDT on April 18, 2014, and NASA's Solar Dynamics Observatory captured images of the event. Solar flares are powerful bursts of radiation. Harmful ...

Impact glass stores biodata for millions of years

12 hours ago

(Phys.org) —Bits of plant life encapsulated in molten glass by asteroid and comet impacts millions of years ago give geologists information about climate and life forms on the ancient Earth. Scientists ...

The importance of plumes

12 hours ago

The Hubble Space Telescope is famous for finding black holes. It can pick out thousands of galaxies in a patch of sky the size of a thumbprint. The most powerful space telescope ever built, the Hubble provided ...

Ceres and Vesta Converge in Virgo

15 hours ago

Don't let them pass you by. Right now and continuing through July, the biggest and brightest asteroids will be running on nearly parallel tracks in the constellation Virgo and so close together they'll easily ...

User comments : 0

More news stories

Impact glass stores biodata for millions of years

(Phys.org) —Bits of plant life encapsulated in molten glass by asteroid and comet impacts millions of years ago give geologists information about climate and life forms on the ancient Earth. Scientists ...