State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China, Key Laboratory of Biology and Genetic Improvement of Maize in Southwest Region of Ministry of Agriculture, Maize Research Institute, Sichuan Agricultural University, Chengdu 611130, China.
Phytopathology. 2023 Jul;113(7):1317-1324. doi: 10.1094/PHYTO-09-22-0336-R. Epub 2023 Aug 28.
Gibberella ear rot (GER) in maize caused by is one of the most devastating maize diseases reducing grain yield and quality worldwide. The genetic bases of maize GER resistance remain largely unknown. Using artificial inoculation across multiple environments, the GER severity of an association panel consisting of 316 diverse inbred lines was observed with wide phenotypic variation. In the association panel, a genome-wide association study using a general linear model identified 69 single-nucleotide polymorphisms (SNPs) significantly associated with GER resistance at the threshold of 2.04 × 10, and the average phenotypic variation explained (PVE) of these SNPs was 5.09%. We also conducted a genome-wide association study analysis using a mixed linear model at a threshold of 1.0 × 10, and 16 significantly associated SNPs with an average PVE of 4.73% were detected. A combined general linear model and mixed linear model method obtained 10 co-localized significantly associated SNPs linked to GER resistance, including the most significant SNP (PZE-105079915) with the greatest PVE value, 9.07%, at bin 5.05 following 10 candidate genes. These findings are significant for the exploration of the complicated genetic variations in maize GER resistance. The regions and genes identified herein provide a list of candidate targets for further investigation, in addition to the elite germplasm resources that can be used for breeding GER resistance in maize.
镰刀菌穗腐病（GER）是由 引起的，是玉米最具破坏性的疾病之一，它会降低全球范围内的玉米产量和质量。玉米 GER 抗性的遗传基础在很大程度上尚不清楚。通过在多个环境中进行人工接种，观察到由 316 个不同自交系组成的关联群体的 GER 严重程度，表现出广泛的表型变异。在关联群体中，使用一般线性模型进行全基因组关联研究，在 2.04×10 的阈值下，鉴定出与 GER 抗性显著相关的 69 个单核苷酸多态性（SNP），这些 SNP 的平均表型变异解释率（PVE）为 5.09%。我们还使用混合线性模型在 1.0×10 的阈值下进行了全基因组关联研究分析，检测到 16 个与 GER 抗性显著相关的 SNP，平均 PVE 为 4.73%。使用一般线性模型和混合线性模型的组合方法获得了 10 个与 GER 抗性相关的共定位显著相关 SNP，包括在 bin 5.05 处与最大 PVE 值 9.07%相关的最显著 SNP（PZE-105079915），该 SNP 位于第 10 个候选基因之后。这些发现对于探索玉米 GER 抗性的复杂遗传变异具有重要意义。鉴定出的区域和基因为进一步研究提供了候选目标列表，此外还提供了可用于玉米 GER 抗性育种的优良种质资源。
