Sesame (Sesamum indicum L.) is an oilseed crop challenged by many biotic stresses. Charcoal rot caused by Macrophomina phaseolina (MP) is one of the most devastating diseases of sesame. Till date, molecular mechanisms of resistance to charcoal rot in sesame is not yet reported. In this study, two sesame variety GT-10 (resistant) and RT-373 (susceptible) were identified with contrasting disease incidence when infected with MP. To get the molecular insight, root samples were collected at 0, 24, 48- and 72-h post inoculation (hpi) with the pathogen and generated RNAseq data was analyzed. A total of 1153 and 1226 differentially expressed genes (DEGS) were identified in GT-10 and RT-373, respectively. During the inoculation with MP, resistant genotype showed high number DEGs at early time point of 24 hpi and when compared to late expression in susceptible genotype at 48 hpi. Distinct clusters were represented for each time period represented by cytochrome P450 83B1-like, single anchor, hypothetical protein C4D60, kirola like and heat shock proteins in the resistant genotype contributing for resistance. Analysis of differentially expressed genes, catalogued the genes involved in synthesis of pathogenesis-related (PR) proteins, MYB, WRKY, leucine zipper protein, bHLH, bZIP and NAC transcription factors, ABC transporters (B, C and G subfamily), glutathione metabolism, secondary metabolites, fatty acid biosynthesis and phytohormones like auxin, abscisic acid, ethylene and gibberellic acid. Additionally, in the resistant response we have found three unique GO terms including ATP binding, ribonucleotide binding and nucleic acid binding in molecular function category. The molecular clues generated through this work will provide an important resource of genes contributing for disease resistance and could prioritize genes for functional validation in the important oil crop.

芝麻 ( Sesamum indicum L.) 是一种油料作物，受到许多生物胁迫的挑战。Macrophomina phaseolina引起的木炭腐烂（MP）是芝麻最具破坏性的病害之一。迄今为止，芝麻抗炭腐的分子机制尚未见报道。在这项研究中，两种芝麻品种 GT-10（抗性）和 RT-373（易感）在感染 MP 时具有不同的发病率。为了获得分子洞察力，在病原体接种后 0、24、48 和 72 小时 (hpi) 收集根样本，并分析生成的 RNAseq 数据。在 GT-10 和 RT-373 中分别鉴定出 1153 和 1226 个差异表达基因 (DEGS)。在用 MP 接种期间，抗性基因型在 24 hpi 的早期时间点显示高数量的 DEG，与在 48 hpi 的易感基因型中的晚期表达相比。以细胞色素 P450 83B1 样表示的每个时间段表示不同的簇，抗性基因型中的单锚、假设蛋白 C4D60、kirola 样和热休克蛋白有助于抗性。差异表达基因分析，对参与致病相关（PR）蛋白、MYB、WRKY、亮氨酸拉链蛋白、bHLH、bZIP和NAC转录因子、ABC转运蛋白（B、C和G亚家族）、谷胱甘肽代谢的基因进行分类、次生代谢物、脂肪酸生物合成和植物激素，如生长素、脱落酸、乙烯和赤霉酸。此外，在抗性反应中，我们在分子功能类别中发现了三个独特的 GO 术语，包括 ATP 结合、核糖核苷酸结合和核酸结合。