Effects of 60Co-γ radiation on seed germination of Glycyrrhiza uralensis under Na2SO4 stress

In order to select the optimum 60Co-γ radiation dose to improve salt-tolerance of Glycyrrhiza uralensis, the present study explored the effects of 60Co-γ radiation on seed germination, accumulated germination percentage and germination index of G. uralensis under different Na2SO4 stress treatments. The results showed that seed germination percentage and germination index decreased and germination time delayed with the increase of salt concentration. However, seed germination percentage of G. uralensis exposed to 60Co-γ radiation and then treated with high Na2SO4 stress was significantly higher than that of control， which indicated that 60Co-γ radiation could effectively improve seed germination percentage under Na2SO4 treatments. These results suggested that different 60Co-γ rays radiation should be employed based on the concentration of Na2SO4 in soil. Especially, seeds of G. uralensis exposed to the 100 Gy radiation treatment showed higher tolerance to Na2SO4 stress.