Genomics and Molecular Breeding Lab, Global Centre of Excellence on Millets (Shree Anna), ICAR-Indian Institute of Millets Research, Hyderabad 500030, India.
Division of Plant Pathology, ICAR-Indian Agricultural Research Institute, New Delhi 110012, India.
Int J Mol Sci. 2024 Nov 9;25(22):12048. doi: 10.3390/ijms252212048.
Foliar blast, caused by , poses a major challenge to pearl millet ( (L.) R. Br) production, leading to severe yield losses, particularly in rainfed ecologies. This study aimed to elucidate the genetic basis of blast resistance through a genome-wide association study (GWAS) involving 281 diverse pearl millet inbreds. GWAS panel was phenotyped for blast resistance against three distinct isolates of collected from Delhi, Gujarat, and Rajasthan locations, revealing a significant variability with 16.7% of the inbreds showing high resistance. Bayesian information and linkage disequilibrium iteratively nested keyway (BLINK) and Multi-Locus Mixed Model (MLMM) models using transformed means identified 68 significant SNPs linked to resistance, with hotspots for resistance-related genes on chromosomes 1, 2, and 6. These regions harbor genes involved in defense mechanisms, including immune response, stress tolerance, signal transduction, transcription regulation, and pathogen defense. Genes, namely , , , , , , and various transcription factors such as and , played a crucial role in the stress-responsive pathways. Analyses of transporter proteins, redox processes, and structural proteins revealed additional mechanisms contributing to blast resistance. This study offers valuable insights into the complex genetic architecture of blast resistance in pearl millet, offering a solid foundation for marker-assisted breeding programs and gene-editing experiments.
叶瘟由 引起,给珍珠粟((L.)R. Br)生产带来重大挑战,导致严重的产量损失,特别是在雨养生态系统中。本研究旨在通过全基因组关联研究(GWAS)阐明抗瘟的遗传基础,该研究涉及 281 个不同的珍珠粟自交系。GWAS 小组对来自德里、古吉拉特邦和拉贾斯坦邦的三个不同 分离株的叶瘟抗性进行了表型分析,发现具有显著的变异性,16.7%的自交系表现出高抗性。贝叶斯信息和连锁不平衡迭代嵌套关键(BLINK)和多基因混合模型(MLMM)模型使用转换均值鉴定了与抗性相关的 68 个显著 SNP,在染色体 1、2 和 6 上存在抗性相关基因的热点。这些区域包含参与防御机制的基因,包括免疫反应、应激耐受、信号转导、转录调控和病原体防御。基因 、 、 、 、 、 和各种转录因子,如 和 ,在应激响应途径中发挥着关键作用。对转运蛋白、氧化还原过程和结构蛋白的分析揭示了对抗瘟性的额外机制。本研究深入了解了珍珠粟抗瘟性的复杂遗传结构,为标记辅助育种计划和基因编辑实验提供了坚实的基础。