Study on Low-cadmium Rice Mutants Induced by ¹²C⁶⁺ Ion Beam

Screening low-cadmium rice cultivar is the most directly and effective way to control cadmium content in rice grain. We screened low-cadmium rice mutant of M2 generation exposed in different Cd concentration (the pool contaminated with 19.8 mg Cd·kg^-1 and the paddy field contaminated with 2.721 mg Cd·kg^-1) from rice mutants(9311, Oryza sativa L) induced by ¹²C⁶⁺ ion beam, and explored the mutation rate of ¹²C⁶⁺ ion beam irradiation and the screening efficiency of different Cd concentration exposed, all of the detections were carried out by Graphite Furnace Atomic Absorption Spectrum(GFAAS). The results showed that the mutation rate is 3:398%±0:009(P<0:05) and high Cd concentration exposed has more efficiency in screening low-Cd rice mutant. Correlation analysis show significant correlation of Cd in rice grain between M2 and M3 generations, r=0:8210(P<0:01); We obtained 23 mutant strains with significant Cd concentration difference and they had a great genetic stability. Among them, three strains' Cd concentrations were lower than the national standard (0.2 mg·kg^-1). They can used for further study on cultivating new rice varieties of low Cd accumulation in rice gain.