Yuan Meng, Zeng Qingdong, Hua Lei, Chen Shisheng, Wu Jianhui, Zhao Shuqing, Li Mengyu, Ren Xiaopeng, Ma Linfei, Liu Zihan, Wang Kaixuan, Sun Manli, Yan Hongfei, Kang Zhensheng, Han Dejun, Wang Xiaodong
State Key Laboratory of North China Crop Improvement and Regulation, College of Plant Protection, Hebei Agricultural University, Baoding, China.
State Key Laboratory of Crop Stress Resistance and High-Efficiency Production, College of Plant Protection, Northwest A&F University, Xianyang, China.
Mol Plant Pathol. 2025 Jun;26(6):e70103. doi: 10.1111/mpp.70103.
Bipolaris sorokiniana is a prevalent fungal pathogen that resides in the soil and affects various parts of wheat, leading to diseases such as spot blotch, common root rot, head blight and black point. The genetic mechanisms that confer resistance in wheat against this pathogen are not completely known. In this research, 1302 wheat germplasms from around the world were evaluated for resistance to spot blotch at the seedling stage, and it was found that merely 3.8% displayed moderate or better resistance. A genome-wide association study (GWAS) employing high-density 660K single-nucleotide polymorphism (SNP) data pinpointed a segment on chromosome 1BL (621.2-674.0 Mb) containing nine SNPs that are significantly linked to spot blotch resistance, named Qsb.hebau-1BL. RNA sequencing and reverse transcription-quantitative PCR analyses demonstrated that the gene TraesCS1B02G410300, which codes for nicotinamide-adenine dinucleotide phosphate-binding oxidoreductase (TaNADPO), was markedly upregulated by B. sorokiniana. Five SNP variations were identified in the promoter region of TaNADPO in wheat lines with or without Qsb.hebau-1BL. Wheat lines that overexpressed TaNADPO exhibited increased resistance to spot blotch and higher accumulation of reactive oxygen species (ROS). In contrast, knockout EMS mutants of Triticum turgidum TdNADPO (tdnadpo-K2561, Gln125*) and TaNADPO (tanadpo-J10516796, splice donor variant) showed diminished resistance and lower ROS levels. In conclusion, TaNADPO is a key gene for resistance against B. sorokiniana, providing essential information for the development of spot blotch-resistant wheat varieties through molecular breeding techniques.
索氏平脐蠕孢是一种常见的真菌病原体，存在于土壤中，可影响小麦的各个部位，引发诸如叶斑病、普通根腐病、穗枯病和黑胚病等病害。小麦对这种病原体产生抗性的遗传机制尚不完全清楚。在本研究中，对来自世界各地的1302份小麦种质进行了苗期叶斑病抗性评估，发现仅有3.8%表现出中等或更强的抗性。一项利用高密度660K单核苷酸多态性（SNP）数据进行的全基因组关联研究（GWAS）确定了1BL染色体上一个621.2 - 674.0 Mb的区域，该区域包含9个与叶斑病抗性显著相关的SNP，命名为Qsb.hebau - 1BL。RNA测序和逆转录定量PCR分析表明，编码烟酰胺腺嘌呤二核苷酸磷酸结合氧化还原酶（TaNADPO）的基因TraesCS1B02G410300在索氏平脐蠕孢作用下显著上调。在具有或不具有Qsb.hebau - 1BL的小麦品系中，TaNADPO启动子区域鉴定出5个SNP变异。过表达TaNADPO的小麦品系对叶斑病的抗性增强，活性氧（ROS）积累增加。相反，硬粒小麦TdNADPO（tdnadpo - K2561，Gln125*）和TaNADPO（tanadpo - J10516796，剪接供体变体）的敲除EMS突变体表现出抗性减弱和ROS水平降低。总之，TaNADPO是抗索氏平脐蠕孢的关键基因，为通过分子育种技术培育抗叶斑病小麦品种提供了重要信息。
