Chinese Bulletin of Botany ›› 2022, Vol. 57 ›› Issue (2): 157-170.DOI: 10.11983/CBB21216

• EXPERIMENTAL COMMUNICATIONS • Previous Articles     Next Articles

QTL Mapping and Candidate Gene Analysis of Vitamin E in Rice Grain

Hanfei Ye1, Wenjing Yin1, Yian Guan1, Kairu Yang1, Qianyu Chen1, Shuying Yu1, Xudong Zhu2, Dedong Xin1, Wei Zhang1,*(), Yuexing Wang2,*(), Yuchun Rao1()   

  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
  • Received:2021-12-12 Accepted:2022-01-20 Online:2022-03-01 Published:2022-03-24
  • Contact: Wei Zhang,Yuexing Wang,Yuchun Rao

Abstract: Vitamin E (VE) is an important index of rice nutritional quality. Rice (Oryza sativa) is the most widely planted crop in China. To increase rice VE content is a convenient and effective way to improve its nutrient composition. In this study, 120 recombinant inbred line (RIL) populations were constructed with indica rice HZ as male parent and japonica rice Nekken2 as female parent. The content of vitamin E isomer in the population was determined by high performance liquid chromatography (HPLC). Quantitative trait loci (QTL) mapping was carried out based on the constructed high-density molecular genetic map. After pedigree analysis, 122 VE related QTLs were identified, which were distributed on 12 chromosomes. Some loci have high LOD scores, such as qT3α/to2-1 with 10.32 LOD score, qT3α2-1 of 9.91 LOD score. There are multiple major QTLs associated with the content of different conformations, and some VE biosynthesis genes are within the intervals, e.g., OsGGR1, OsGGR2, OsTC and OsγTMT. The expression of these genes were analyzed by qRT-PCR. The results showed that their expression in HZ was significantly higher than that in Nekken2. It is speculated that the high expression of these genes is the reason of why tocopherol and tocotrienol in HZ are higher than in Nekken2. The number of QTLs and the scores of LOD are large, which provides a molecular basis for further screening and cultivating rice varieties with high VE content also conductive to clarify the molecular regulation mechanism of rice VE biosynthesis through QTLs.

Key words: rice, vitamin E, QTL mapping, candidate genes, rice quality