Natural variation in maize gene ZmSBR1 confers seedling resistance to Fusarium verticillioides
Yunxia Song,
Peipei Ma,
Jingyang Gao,
Chaopei Dong,
Zhao Wang,
Yifan Luan,
Jiafa Chen,
Doudou Sun,
Pei Jing,
Xuecai Zhang,
Weibin Song,
Zijian Zhou,
Jianyu Wu
Affiliations
Yunxia Song
College of Agronomy, Henan Agricultural University, Zhengzhou 450002, Henan, China
Peipei Ma
College of Life Sciences, Henan Agricultural University, Zhengzhou 450002, Henan, China
Jingyang Gao
College of Agronomy, Henan Agricultural University, Zhengzhou 450002, Henan, China
Chaopei Dong
College of Agronomy, Henan Agricultural University, Zhengzhou 450002, Henan, China
Zhao Wang
College of Agronomy, Henan Agricultural University, Zhengzhou 450002, Henan, China
Yifan Luan
College of Agronomy, Henan Agricultural University, Zhengzhou 450002, Henan, China
Jiafa Chen
College of Life Sciences, Henan Agricultural University, Zhengzhou 450002, Henan, China
Doudou Sun
College of Life Sciences, Henan Agricultural University, Zhengzhou 450002, Henan, China
Pei Jing
College of Life Sciences, Henan Agricultural University, Zhengzhou 450002, Henan, China
Xuecai Zhang
Global Maize Program, International Maize and Wheat Improvement Center (CIMMYT), Apdo 6-641, 06600 Mexico, DF, Mexico
Weibin Song
National Maize Improvement Center, Department of Plant Genetics and Breeding, China Agricultural University, Beijing 100193, China
Zijian Zhou
College of Life Sciences, Henan Agricultural University, Zhengzhou 450002, Henan, China; Corresponding authors.
Jianyu Wu
College of Agronomy, Henan Agricultural University, Zhengzhou 450002, Henan, China; College of Life Sciences, Henan Agricultural University, Zhengzhou 450002, Henan, China; Corresponding authors.
Maize seedling blight caused by Fusarium verticillioides is a widely occurring maize disease, but the genetics and mechanisms of resistance are not well understood. In this study, GWAS performed by MLM and 3VmrMLM identified 40 and 20 QTNs, associated with seedling blight resistance. These methods identified 49 and 36 genes, respectively. Functional verification of candidate gene ZmSBR1 identified by both methods showed that the resistance of a mutant line to seedling blight decreased by 0.37 grade points after inoculation with F. verticillioides, compared with the WT. The length of the stem rot lesion caused by F. verticillioides increased by 86% in mutant seedlings, and the relative length of the adult plant stalk rot increased by 35% in mutant plants compared to the wild type after inoculation with Fusarium graminearum. Transcriptome analysis showed that expression of defense-related genes after inoculation was down-regulated in the mutant compared to the wild type, synthesis of secondary metabolites associated with resistance was reduced, and the immune response triggered by PAMP decreased, resulting in decreased resistance of mutant maize seedlings. Candidate gene association analysis showed that most maize inbred lines carried the susceptible haplotype. A functional PCR marker was developed. The results demonstrated that ZmSBR1 conferred resistance to multiple Fusarium diseases at the seedling and adult growth stages and had important application value in breeding.
