Genetic Effect Analysis Of Cadmium Accumulation Gene Of Japonica

Cadmium is one of the most harmful heavy metals.Therefore,it is of great significance to reduce the cadmium content in rice to ensure people's life and health.We use two low Cd accumulation of Japonica rice?IRTA129,NG6954?and two high cadmium accumulation of Indica rice?628S,Xiangling 9311?constructed genetic population to verify the effect of Japonica low Cd gene accumulation of in Indica genetic background.The results are as follows:?1?Near isogenic lines from IRTA129 and Xiangling628S were constructed by three residual heterozygous to verify the genetic effects of OsHMA3 and the gene cluster?OsHMA3,OsNramp5,OsNramp1?in IRTA129.The result of double factor variance in Cd content among three near isogenic lines showed that OsHMA3 in NIL1 and NIL2 of IRTA129 had a significant effect on reducing cadmium content in brown rice,but the gene cluster?OsHMA3,OsNramp5,OsNramp1?had a contrary result.This may be due to the heading stage of Ghd7,which is closely related to OsNramp1.?2?RILs from IRTA129 and Xiangling628S were constructed to verify the genetic effects of many QTLs in IRTA129.We found that Cd content in brown rice of RILs within markers,Nramp5-3,LCD-1,RM13899,RM18589,had a significant difference,while no significant difference in the growth period.BC₂F₂ and BC₃F₂ group from 9311 and IRTA129,NG6954 respectively were constructed to verify the genetic effect of gene cluster?OsHMA3,OsNramp5,OsNramp1?in IRTA129 and NG6954 with 9311 genetic background.The results indicated that the gene cluster?OsHMA3,OsNramp5,OsNramp1?of IRTA129 and NG6954 should reduce the cadmium content in brown rice,which consistented with the results of recombinant inbred lines.?3?Total genomic sequence of OsHMA3,OsNramp5,OsNramp1 and Ghd7 in parents were cloned to analysis the predicted amino acid.The alignment of proteins in OsHMA3,OsNRAMP5,OsNRAMP1 and GHD7 showed that diversity loci were found in related materials,explaining differences in cadmium absorption characteristics of different materials.All results showed that the low Cd gene accumulation in Japonica rice could play a corresponding role in Indica background,which were benefited for MAS?Marker assisted selection?of cadmium high accumulation in Indica rice cultivars.