Disease resistance in Brassica juncea has been shown against several diseases including blackleg, white rust, hypocotyl rot, turnip mosaic virus, leaf blight, black rot, and Alternaria blight. The identification of disease resistance genes is important to develop elite cultivars, which can survive exposure to these diseases. The largest family of resistance genes are nucleotide-binding site leucine-rich repeat genes (NLRs) which are classified into two major subfamilies: toll/interleukin-1 receptor-NLR (TNL) and coiled-coil-NLR (CNL) proteins. Here we present the first study of the genomic organization and evolutionary history of the NLR gene family in B. juncea, with comparative analysis to the diploid progenitors B. rapa and B. nigra. A total of 289 NLR genes were identified in B. juncea, with a ratio of 0.61:1 of TNL to non-TNL genes. The distribution of NLR genes was random and uneven, with chromosome A04 containing no NLR genes. Domain structure analysis revealed that 24% of NLR genes are typical resistance genes containing all three domains (TIR/CC, NBS, LRR), whereas the remaining genes are partially deleted or truncated. A total of 45% NLR genes were found to be physically clustered in the B. juncea genome. The NLR genes were analysed with OrthoFinder which showed that most physical clusters (63%) in B. juncea came from the same orthogroup. This study provides a valuable resource for the identification and characterization of candidate NLR genes for Brassica crop improvement.

已显示芥菜对几种疾病的抗病性，包括黑腿病，白锈病，下胚轴腐烂，芜菁花叶病毒，叶枯病，黑腐病和链霉病。抗病基因的鉴定对于发展优良的品种很重要，这些品种可以在暴露于这些疾病后幸存下来。抵抗基因的最大家族是核苷酸结合位点富含亮氨酸的重复基因（NLR），它们被分为两个主要的亚家族：toll / interleukin-1受体-NLR（TNL）和卷曲螺旋-NLR（CNL）蛋白。在这里，我们介绍了芥菜中NLR基因家族的基因组组织和进化史的首次研究，并与二倍体祖先B. rapa和B. nigra进行了比较分析。。在芥菜芽孢杆菌中总共鉴定出289个NLR基因，TNL与非TNL基因的比率为0.61：1。NLR基因的分布是随机且不均匀的，染色体A04不包含NLR基因。域结构分析显示，有24％的NLR基因是包含所有三个域（TIR / CC，NBS，LRR）的典型抗性基因，而其余基因被部分删除或截短。发现总共45％的NLR基因在聚芥酸杆菌基因组中物理聚集。用OrthoFinder分析了NLR基因，结果表明，芥菜中的大多数物理簇（63％）来自同一正交群。这项研究为鉴定和鉴定甘蓝型油菜作物的候选NLR基因提供了宝贵的资源。