Potential survival of the lichen Caloplaca flavovirescens under high helium-beam doses.
Radiat Environ Biophys
; 58(3): 449-454, 2019 08.
Article
en En
| MEDLINE
| ID: mdl-31222610
ABSTRACT
Testing the limits of survivability in space is the primary focus in astrobiological research. Although a number of previous studies have examined terrestrial life survival in an extraterrestrial environment, only a few have investigated how life systems respond to high doses of alpha cosmic ray, the main component of cosmic rays. We used respiration and photosynthetic rates as indicators of the vital signs of the lichen Caloplaca flavovirescens, which is a symbiotic life form including fungi and algae. Our experiment demonstrated that the photosynthetic rate decreased with increased helium-beam doses, whereas the respiration rate was relatively unaffected. Specifically, under a helium-beam dose greater than 10 Gy, the respiration rate remained nearly constant regardless of further increases in the radiation rate. Our results indicate that the different metabolic systems of terrestrial life forms might exhibit different survival characteristics when they are in space.
Palabras clave
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Radiación Cósmica
/
Relación Dosis-Respuesta en la Radiación
/
Líquenes
Idioma:
En
Revista:
Radiat Environ Biophys
Año:
2019
Tipo del documento:
Article
País de afiliación:
Japón