Identification and fine-mapping of a QTL, qMrdd1, that confers recessive resistance to maize rough dwarf disease

BMC Plant Biology

Research Article

Yongfu Tao¹  Qingcai Liu¹  Jianrong Ye¹  Mingliang Xu¹  Baobao Wang¹  Jinsheng Lai¹  Xinyi Huang¹  Honghong Wang²  Yanjun Zhang²  Baoshen Liu² 

[1] National Maize Improvement Center, China Agricultural University, 2 West Yuanmingyuan Road, 100193, Beijing, People’s Republic of China;State Key Laboratory of Crop Biology, Shandong Agricultural University, 61 Daizong Street, 271018, Shandong, People’s Republic of China;

关键词: Maize;    MRDD;    QTL;    Fine-mapping;    Recombinant-derived progeny test;   

DOI  :  10.1186/1471-2229-13-145

 received in 2013-05-19, accepted in 2013-09-27,  发布年份 2013

来源: Springer

【 摘 要 】

BackgroundMaize rough dwarf disease (MRDD) is a devastating viral disease that results in considerable yield losses worldwide. Three major strains of virus cause MRDD, including maize rough dwarf virus in Europe, Mal de Río Cuarto virus in South America, and rice black-streaked dwarf virus in East Asia. These viral pathogens belong to the genus fijivirus in the family Reoviridae. Resistance against MRDD is a complex trait that involves a number of quantitative trait loci (QTL). The primary approach used to minimize yield losses from these viruses is to breed and deploy resistant maize hybrids.ResultsOf the 50 heterogeneous inbred families (HIFs), 24 showed consistent responses to MRDD across different years and locations, in which 9 were resistant and 15 were susceptible. We performed trait-marker association analysis on the 24 HIFs and found six chromosomal regions which were putatively associated with MRDD resistance. We then conducted QTL analysis and detected a major resistance QTL, qMrdd1, on chromosome 8. By applying recombinant-derived progeny testing to self-pollinated backcrossed families, we fine-mapped the qMrdd1 locus into a 1.2-Mb region flanked by markers M103-4 and M105-3. The qMrdd1 locus acted in a recessive manner to reduce the disease-severity index (DSI) by 24.2–39.3%. The genetic effect of qMrdd1 was validated using another F6 recombinant inbred line (RIL) population in which MRDD resistance was segregating and two genotypes at the qMrdd1 locus differed significantly in DSI values.ConclusionsThe qMrdd1 locus is a major resistance QTL, acting in a recessive manner to increase maize resistance to MRDD. We mapped qMrdd1 to a 1.2-Mb region, which will enable the introgression of qMrdd1-based resistance into elite maize hybrids and reduce MRDD-related crop losses.

【 授权许可】

Unknown   
© Tao et al.; licensee BioMed Central Ltd. 2013. This article is published under license to BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.