水稻籽粒镉低积累资源挖掘及其新材料创制

稻米镉超标已经成为引起社会广泛关注的食品安全问题,生产上迫切需要选育适宜在镉污染地区种植的低镉积累水稻新品种。通过对国内外275份水稻资源进行筛选,挖掘到在重度镉污染田籽粒镉低积累材料珞红3A和珞红4A。全基因组高通量测序结果表明,在珞红4A的第7号染色体上有一段长度为408481 bp的片段(Org)缺失,且在该缺失处插入了一段长度为2980 bp的序列(Tons)。共分离试验发现,Tons与水稻籽粒镉低积累存在紧密关联。本研究建立了Tons分子标记检测体系,进一步利用该体系在珞红4A与IR28杂交的F2群体中获得了低镉新材料Tonys,并提出了一套选育籽粒镉低积累水稻新品种的方法。

Excavation of Rice Resources with Low Cadmium Accumulation in Grains and Development of New Materials

Excessive cadmium in rice grains has become a food safety issue that has been attracting a widespread concern in society.There is an urgent need to develop new low-cadmium rice varieties suitable for planting in the areas with cadmium pollution.By screening 275 rice resources collected in and outside China,the materials Luohong 3 A and Luohong 4 A were found to have the characteristic of low cadmium accumulation in grains under the conditions of severe cadmium pollution.The whole genome high-throughput sequencing indicated that Luohong 4 A had a fragment deletion of 408481 bp(Org)which was replaced by a fragment of 2980 bp(Tons)on Chromosome 7.The cosegregation experiment showed that Tons was closely linked to low cadmium accumulation in rice grains.A detecting system with the molecular markers of Tons was developed,and a new low-cadmium material,Tonys,was obtained by use of the molecular marker system in the F2 population of the cross between Luohong 4 A and IR28.Furthermore,a methodology for developing new rice varieties with low cadmium accumulation in grains was put forward.