title: Fine mapping of a quantitative trait locus conferring resistance to maize rough dwarf disease.
abstract: A QTL qMrdd8 that confers resistance to MRDD was fine mapped into an interval of 347 kb; one SNP and two InDels identified in the interval were significantly associated with resistance to MRDD. Maize rough dwarf disease (MRDD) is highly prevalent in the summer maize-growing areas in China, and leads to significant yield losses in maize (Zea mays L.). In this study, the quantitative trait locus (QTL) qMrdd8, which confers resistance to MRDD, was fine mapped. Initially, qMrdd8 was consistently identified in the interval between the simple sequence repeat markers umc1617 and phi121 in three F2sub-populations derived from a cross between the resistant recombinant inbred line NL203 and the susceptible line B73. Subsequently, qMrdd8 was fine mapped into an interval of 347 kb defined by the markers IDRQ2 and IDRQ20 using a recombinant-derived progeny test strategy. Based on single nucleotide polymorphism (SNP) genotypes identified using the MaizeSNP50 BeadChip, a long haplotype including qMrdd8 was identified in four resistant inbred lines. One SNP, the 2549-bp insertion/deletion polymorphism (InDel) InDel25, and the 2761-bp InDel27, which all were significantly associated with resistance to MRDD in a set of 226 maize inbred lines (P < 0.05), were detected within qMrdd8. Furthermore, two candidate genes, CG1 and CG2, were detected in the interval using RNA sequencing (RNA-Seq), and InDel25 was localized within the candidate gene CG1. In conclusion, the fine mapping of qMrdd8 will be helpful in cloning the resistance gene, and the three polymorphic markers identified in this study could be used to improve MRDD resistance via a marker-assisted selection approach.
authors.affiliation: Institute of Crop Science, Chinese Academy of Agricultural Sciences, No. 12 Zhongguancun South Street, Haidian District, Beijing, 100081, China.
authors.forename: Changlin
authors.initials: C
authors.lastname: Liu
authors.affiliation: Institute of Crop Science, Chinese Academy of Agricultural Sciences, No. 12 Zhongguancun South Street, Haidian District, Beijing, 100081, China.
authors.forename: Jinge
authors.initials: J
authors.lastname: Hua
authors.affiliation: Northeast Agricultural University, Harbin, 150000, Heilongjiang, China.
authors.forename: Chang
authors.initials: C
authors.lastname: Liu
authors.affiliation: Institute of Crop Science, Chinese Academy of Agricultural Sciences, No. 12 Zhongguancun South Street, Haidian District, Beijing, 100081, China.
authors.forename: Degui
authors.initials: D
authors.lastname: Zhang
authors.affiliation: Institute of Crop Science, Chinese Academy of Agricultural Sciences, No. 12 Zhongguancun South Street, Haidian District, Beijing, 100081, China.
authors.forename: Zhuanfang
authors.initials: Z
authors.lastname: Hao
authors.affiliation: Institute of Crop Science, Chinese Academy of Agricultural Sciences, No. 12 Zhongguancun South Street, Haidian District, Beijing, 100081, China.
authors.forename: Hongjun
authors.initials: H
authors.lastname: Yong
authors.affiliation: Institute of Crop Science, Chinese Academy of Agricultural Sciences, No. 12 Zhongguancun South Street, Haidian District, Beijing, 100081, China.
authors.forename: Chuanxiao
authors.initials: C
authors.lastname: Xie
authors.affiliation: Institute of Crop Science, Chinese Academy of Agricultural Sciences, No. 12 Zhongguancun South Street, Haidian District, Beijing, 100081, China.
authors.forename: Mingshun
authors.initials: M
authors.lastname: Li
authors.affiliation: Institute of Crop Science, Chinese Academy of Agricultural Sciences, No. 12 Zhongguancun South Street, Haidian District, Beijing, 100081, China.
authors.forename: Shihuang
authors.initials: S
authors.lastname: Zhang
authors.affiliation: Institute of Crop Science, Chinese Academy of Agricultural Sciences, No. 12 Zhongguancun South Street, Haidian District, Beijing, 100081, China. wengjianfeng@caas.cn.
authors.forename: Jianfeng
authors.initials: J
authors.lastname: Weng
authors.affiliation: Institute of Crop Science, Chinese Academy of Agricultural Sciences, No. 12 Zhongguancun South Street, Haidian District, Beijing, 100081, China. lixinhai@caas.cn.
authors.forename: Xinhai
authors.initials: X
authors.lastname: Li
mesh_terms: D002874:Chromosome Mapping; D060467:Disease Resistance / Q000235:genetics*; D008040:Genetic Linkage; D005838:Genotype; D006239:Haplotypes; D054643:INDEL Mutation; D010641:Phenotype; D000069600:Plant Breeding; D010935:Plant Diseases / Q000235:genetics* / Q000821:virology; D010942:Plant Viruses; D020641:Polymorphism, Single Nucleotide; D040641:Quantitative Trait Loci; D003313:Zea mays / Q000235:genetics* / Q000821:virology