QTL Mapping by Whole Genome Re-sequencing and Analysis of Candidate Genes for Nitrogen Use Efficiency in Rice

Frontiers in Plant Science

Yanyan Wu¹  Faqian Xiong²  Ju Gao³  Danting Li⁴  Guofu Deng⁴  Zongqiong Zhang⁴  Yu Zeng⁴  Baoxuan Nong⁴  Xinghai Yang⁴  Xiuzhong Xia⁴ 

[1] Biotechnology Research Institute, Guangxi Academy of Agricultural SciencesNanning, China;Cash Crops Research Institute, Guangxi Academy of Agricultural SciencesNanning, China;Guangxi Crop Genetic Improvement and Biotechnology Laboratory, Guangxi Academy of Agricultural SciencesNanning, China;Rice Research Institute, Guangxi Academy of Agricultural SciencesNanning, China;

关键词: rice;    nitrogen use efficiency;    whole genome re-sequencing;    QTL;    candidate genes;   

DOI  :  10.3389/fpls.2017.01634

来源: DOAJ

【 摘 要 】

Nitrogen is a major nutritional element in rice production. However, excessive application of nitrogen fertilizer has caused severe environmental pollution. Therefore, development of rice varieties with improved nitrogen use efficiency (NUE) is urgent for sustainable agriculture. In this study, bulked segregant analysis (BSA) combined with whole genome re-sequencing (WGS) technology was applied to finely map quantitative trait loci (QTL) for NUE. A key QTL, designated as qNUE6 was identified on chromosome 6 and further validated by Insertion/Deletion (InDel) marker-based substitutional mapping in recombinants from F2 population (NIL-13B4 × GH998). Forty-four genes were identified in this 266.5-kb region. According to detection and annotation analysis of variation sites, 39 genes with large-effect single-nucleotide polymorphisms (SNPs) and large-effect InDels were selected as candidates and their expression levels were analyzed by qRT-PCR. Significant differences in the expression levels of LOC_Os06g15370 (peptide transporter PTR2) and LOC_Os06g15420 (asparagine synthetase) were observed between two parents (Y11 and GH998). Phylogenetic analysis in Arabidopsis thaliana identified two closely related homologs, AT1G68570 (AtNPF3.1) and AT5G65010 (ASN2), which share 72.3 and 87.5% amino acid similarity with LOC_Os06g15370 and LOC_Os06g15420, respectively. Taken together, our results suggested that qNUE6 is a possible candidate gene for NUE in rice. The fine mapping and candidate gene analysis of qNUE6 provide the basis of molecular breeding for genetic improvement of rice varieties with high NUE, and lay the foundation for further cloning and functional analysis.

【 授权许可】

Unknown