Effects of the Space Environment on Silkworm Development Time

As aviation technology has developed, there has been more emphasis on exploitation and utilization of the space frontier. The lepidopteran insect Bombyx mori has advantages, including small body size, light weight, short life cycle, and well-characterized genetics, when used as a model for biological investigations in space compared with other animals. In preparation for experiments in space, we carried out a simulation experiment, and the number of embryos and the culture temperature and humidity were optimized. The silkworm incubator was launched with China’s SJ-10 recoverable microgravity experimental satellite and was in orbit for 12 days and 15 h in 2016. The embryos were cultured in space. Images of the silkworm embryos were obtained during flight. The embryos cultured in space hatched properly after returning to the ground, but silkworm larva obtained from cultures grown on the SJ-10 satellite grew more rapidly than the ground control group. Analyses of subsequent generations and genome, transcriptome, and proteome analyses are ongoing.