Department of Botany, Institute of Science, Banaras Hindu University, Varanasi, India.
Department of Genetics and Plant Breeding, Institute of Agricultural Sciences, Banaras Hindu University, Varanasi, India.
PLoS One. 2020 Oct 5;15(10):e0240029. doi: 10.1371/journal.pone.0240029. eCollection 2020.
Lesion mimic (Lm) mutants display hypersensitive responses (HR) without any pathogen attack; their symptoms are similar to those produced by a pathogen and result in cell death. In wheat, such mutants have been reported to be resistant against leaf rust due to their biotrophic nature. However, Lm mutants tend to encourage spot blotch (SB) disease caused by Bipolarissorokiniana since dead cells facilitate pathogen multiplication. In this study, 289 diverse wheat germplasm lines were phenotyped in three consecutive growing seasons (2012-2015). Genotype data was generated using the Illumina iSelect beadchip assay platform for wheat germplasm lines. A total of 13,589 single-nucleotide polymorphisms (SNPs) were selected andused for further association mapping. Lm was positively associated with Area Under Disease Progress Curve (AUDPC) for SB but negatively with glaucous index (GI), leaf tip necrosis (Ltn) and latent period (LP). Ltn had a negative association with AUDPC and Lm but a positive one with LP. In a genome-wide association study (GWAS), 29 markers were significantly associated with these traits and 27 were an notated. Seven SNP markers associated with Lm were on chromosome 6A; another on 1B was found to be linked with Ltn. Like wise, seven SNP markers were associated with GI; one on chromosome 6A with the others on 6B. Five SNP markers on chromosomes 3B and 3Dwere significantly correlated with LP, while nine SNP markers on chromosomes 5A and 5B were significantly associated with AUDPC for SB. This study is the first to explore the interaction in wheat between Lm mutants and the hemibiotrophic SB pathogen B.sorokiniana.
损伤拟态 (Lm) 突变体在没有任何病原体攻击的情况下表现出过敏反应 (HR)；它们的症状与病原体产生的症状相似，导致细胞死亡。在小麦中，由于其生物营养特性，已报道此类突变体对叶锈病具有抗性。然而，由于死细胞有利于病原体繁殖，Lm 突变体往往会导致由双极座壳引起的斑点病 (SB)。在这项研究中，在三个连续的生长季节（2012-2015 年）中对 289 种不同的小麦种质系进行了表型分析。使用 Illumina iSelect 珠芯片分析平台为小麦种质系生成基因型数据。总共选择了 13589 个单核苷酸多态性 (SNP) 用于进一步的关联作图。Lm 与 SB 的疾病进展曲线下面积 (AUDPC) 呈正相关，但与苍白指数 (GI)、叶尖坏死 (Ltn) 和潜伏期 (LP) 呈负相关。Ltn 与 AUDPC 和 Lm 呈负相关，与 LP 呈正相关。在全基因组关联研究 (GWAS) 中，有 29 个标记与这些性状显著相关，其中 27 个被注释。与 Lm 相关的 7 个 SNP 标记位于 6A 染色体上；另一个位于 1B 的 SNP 标记与 Ltn 相关。同样，与 GI 相关的 7 个 SNP 标记；一个位于 6A 染色体上，其余位于 6B 染色体上。位于 3B 和 3D 染色体上的 5 个 SNP 标记与 LP 显著相关，位于 5A 和 5B 染色体上的 9 个 SNP 标记与 SB 的 AUDPC 显著相关。这项研究首次探索了小麦中 Lm 突变体与半生物营养性 SB 病原体 B. sorokiniana 之间的相互作用。
