The Fusarium fujikuroi species complex (FFSC) is an economically important monophyletic lineage in the genus Fusarium. Incongruence observed among mitochondrial gene trees, as well as the multiple non-orthologous copies of the internal transcribed spacer region of the ribosomal RNA genes, suggests that the origin and history of this complex likely involved interspecies gene flow. Based on this hypothesis, the mitochondrial genomes of non-conspecific species should harbour signatures of introgression or introgressive hybridization. The aim of this study was therefore to search for recombination between the mitochondrial genomes of different species in the FFSC. Using methods based on mt genome sequence similarity, five significant recombinant regions in both gene and intergenic regions were detected. Using coalescent-based methods and the sequences for individual mt genes, various ancestral recombination events between different lineages of the FFSC were also detected. These findings suggest that interspecies gene flow and introgression are likely to have played key roles in the evolution of the FFSC at both ancient and more recent time scales.

中文翻译：

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镰刀菌Fujikuroi物种复合体的线粒体渗入和种间重组。

镰刀镰刀菌（Fusarium fujikuroi）种复合体（FFSC）是镰刀菌属（Fusarium）的经济上重要的单系谱系。线粒体基因树之间观察到不一致，以及核糖体RNA基因内部转录间隔区的多个非直系同源拷贝，表明该复合体的起源和历史可能涉及种间基因流动。基于此假设，非同种物种的线粒体基因组应具有渐渗或渐渗杂交的特征。因此，本研究的目的是寻找FFSC中不同物种的线粒体基因组之间的重组。使用基于mt基因组序列相似性的方法，在基因和基因间区域中检测到五个重要的重组区域。使用基于聚结的方法和单个mt基因的序列，还检测了FFSC不同谱系之间的各种祖先重组事件。这些发现表明，在古代和最近的时间尺度上，种间基因流动和基因渗入都可能在FFSC的进化中起关键作用。