Effects of spaceflight and simulated microgravity on cell sub-microstructure and antioxidant enzyme activity in tomato

Controlled ecological life support systems provide food, air, water, and other basic living resources for crew members on long-duration spaceflight missions. Plants are an important basic requirement of these systems and their biological characteristics in space have very high research value. Based on experiments of spaceflight in Shenzhou 8 spacecraft and simulating microgravity effects on three-dimensional (3-D) clinostat, the biological characteristics of tomato’s leaf cell sub-microstructure and antioxidant enzyme activities were studied and compared in this work. Results showed that leaf cell sub-microstructure of the tomato samples experiencing spaceflight had more changes than that of the samples processed by simulated microgravity effects, and both peroxidase (POD) and superoxide dismutase (SOD) activities increase obviously in both the environments.