Table_S4_Genome_wide_windowed_partial_correlations.csv from Recombination landscape dimorphism and sex chromosome evolution in the dioecious plant <i>Rumex hastatulus</i>

There is growing evidence from diverse taxa for sex differences in the genomic landscape of recombination, but the causes and consequences of these differences remain poorly understood. Strong recombination landscape dimorphism between the sexes could have important implications for the dynamics of sex chromosome evolution because low recombination in the heterogametic sex can favour the spread of sexually antagonistic alleles. Here, we present a sex-specific linkage map and revised genome assembly of Rumex hastatulus and provide the first evidence and characterization of sex differences in recombination landscape in a dioecious plant. We present data on significant sex differences in recombination, with regions of very low recombination in males covering over half of the genome. This pattern is evident on both sex chromosomes and autosomes, suggesting that pre-existing differences in recombination may have contributed to sex chromosome formation and divergence. Our analysis of segregation distortion suggests that haploid selection due to pollen competition occurs disproportionately in regions with low male recombination. We hypothesize that sex differences in the recombination landscape have contributed to the formation of a large heteromorphic pair of sex chromosomes in R. hastatulus, but more comparative analyses of recombination will be important to investigate this hypothesis further.This article is part of the theme issue ‘Sex determination, sex chromosome evolution, and the role of sexual differentiation in land plants’.越来越多来自不同分类群的研究证据表明，重组景观存在性别差异，但这类差异的成因与后果仍未得到充分阐释。两性间显著的重组景观二态性可能对性染色体演化动态产生重要影响，因为异配性别（heterogametic sex）的低重组率会促进性拮抗等位基因（sexually antagonistic alleles）的扩散。本研究针对戟叶酸模（Rumex hastatulus）构建了性别特异性连锁图谱并修订了其基因组组装，同时首次在雌雄异株植物（dioecious plant）中证实了重组景观的性别差异并对其进行了系统表征。我们的研究数据显示重组存在显著性别差异：雄性体内重组率极低的区域覆盖了超过一半的基因组。该模式在性染色体与常染色体（autosomes）上均有体现，表明重组预先存在的差异可能推动了性染色体的形成与分化。我们对分离扭曲（segregation distortion）的分析表明，由花粉竞争（pollen competition）引发的单倍体选择（haploid selection）优先集中发生在雄性低重组区域。我们提出假说：重组景观的性别差异推动了戟叶酸模形成大型异形性染色体对，但未来需开展更多重组相关比较分析以进一步验证该假说。本文隶属于专题合集“性别决定、性染色体演化以及性别分化在陆生植物中的作用”。