Life cycle of arabidopsis in the international space station - Growth direction of the inflorescence stems in the presence of light under microgravity

In the "Space Seed" experiment performed in Kibo module of the International Space Station, growth direction of the inflorescence stem of arabidopsis was examined under space 1 G, μG, and ground 1 G conditions in the presence of light. The stems grew almost upright (vertical to the surface of seedbed) under ground 1 G. Although the stems were primarily upright both under space 1 G and μG, they tilted slightly. The tilting of the stems under space 1 G was indicated to be due to tilting of the artificial gravitational acceleration vectors produced on the centrifuge. The tilting of the stems under μG was suggested to be due to the pressure of directional airflow produced by ventilation.