Chinese Bulletin of Botany ›› 2021, Vol. 56 ›› Issue (1): 25-32.DOI: 10.11983/CBB20148

• EXPERIMENTAL COMMUNICATIONS • Previous Articles     Next Articles

QTL Mapping of Candidate Genes Involved in Cd Accumulation in Rice Grain

Chenyang Pan1, Hanfei Ye1, Weiyong Zhou3, Sheng Wang1, Mengjia Li1, Mei Lu1, Sanfeng Li2, Xudong Zhu2, Yuexing Wang2, Yuchun Rao1,*(), Gaoxing Dai3,*()   

  1. 1College of Chemistry and Life Sciences, Zhejiang Normal University, Jinhua 321004, China
    2State Key Laboratory of Rice Biology, China National Rice Research Institute, Hangzhou 310006, China
    3Guangxi Academy of Agricultural Sciences, Nanning 530007, China
  • Received:2020-08-26 Accepted:2020-11-11 Online:2021-01-01 Published:2021-01-15
  • Contact: Yuchun Rao,Gaoxing Dai


Rice is one of the world’s most important crops, but cadmium (Cd) pollution and Cd accumulation in rice fields pose a serious threat to its yield and quality as well as to human health. How to reduce Cd accumulation in rice has become a major concern. In this study, a japonica rice variety Nekken2 was used as the maternal parent, and an indica rice variety HZ was used as the paternal parent. After F1 generation was obtained by cross-breeding, successive selfings were performed for 120 recombinant inbred lines (RILs) population as the QTL mapping populations. We measured the Cd content in rice grains of each line at the maturity stage. Meanwhile, QTL mapping was performed using genetic map. As a result, a total of 7 QTLs were detected, which were located on chromosome 2, 3, 9, and 12 of rice, with the highest LOD score of 4.97. The qRT-PCR analysis on the candidate genes involved in metal ion stress resistance in these QTL regions showed that the expression level of LOC_Os02g50240, LOC_Os02g52780, LOC_Os09g31200, LOC_Os09g35030 and LOC_Os09g37949 was significantly different from the parents. Combined with the data of concentration of different metal ions in the parents, we speculated that the high expression of LOC_Os02g50240, LOC_Os09g31200 and LOC_Os09g35030 might greatly improve the absorption and tolerance of rice to Cd ion stress. And these genes may be related to the accumulation of Cd in rice grains, and may affect the ability of rice to tolerate Cd stress, which could help for further breeding and screening for rice varieties to tolerate Cd stress, and exploring the molecular regulation mechanism of Cd accumulation in rice.

Key words: rice, cadmium accumulation, QTL mapping, candidate genes, ion stress, genetic map