Biological Effects of Low Energy Ar^+Ion Bombardment on Silkworm Eggs:a Novel Animal Model

In this study, we found for the first time that silkworm eggs were able to survive in vacuum for a long period of time. Subsequently, 10w energy Ar＋ ions with different energies and fluences were used to bombard silkworm eggs so as to explore the resulting biological effects. Results showed that （i） the exposure of silkworm eggs to vacuum within 10 rain did not cause significant impact on the hatching rates, while the irradiation of silkworm eggs by Ar＋ ions of 25 keV or 30 keV with fiuences ranging from 2.6×2.6× 10^15 ion/cm2 to 8×2.6 × 10^15 ion/cm2 caused a significant impact on the hatching rates, and the hatching rates decreased with the increase in the fluence and energy level; （ii） the irradiation of silkworm eggs by Ar＋ ions of 30 keV with a fluence of 8×2.6 × 10^15 ion/cm2 or 9×2.6 × 10^15 ion/cm2 resulted in a noticeable etching on the egg shell surface which could be observed by a scanning electron microscope; and （iii） the irradiation of silkworm eggs by Ar＋ ions of generated several mutant phenotypes which were 30 keV with a fiuence of 9×2.6× 10^15 ion/cm2 observed in the 5th instar silkworms and a moth.