Plant evolution may be triggered by significant chromosome changes. In some plant groups, karyoevolution played an important role, influencing speciation processes. Hohenbergia comprises 48 species distributed through eastern Brazil. Previous cytological information includes few species and only chromosome counts, lacking information about genome size and more accurate karyomorphological investigation. Here, we compare cytomolecular features and genome sizes of 12 Hohenbergia spp. Besides, new measurements of genome sizes of 32 species are reported. All studied species presented 2n = 50, a number prevalent in Bromelioideae. The genome sizes (2C) varied from 0.74 to 1.52 pg. Despite the apparent homogeneity in chromosome number and genome size in Hohenbergia, significant polymorphism was observed in regard to the distribution of CMA⁺/DAPI⁰ bands and sites of 35S and 5S rDNA in metaphase chromosomes. Seven out of 12 analysed species presented heteromorphic pairs regarding 35S rDNA and/or 5S rDNA. Hohenbergia thus shows karyotypic diversity despite the conservation in chromosome number.

中文翻译：

---

Hohenbergia（凤梨科，凤梨科）的基因组大小和染色体数目保守性与核型多样性形成对比

明显的染色体变化可能触发植物的进化。在某些植物群中，核进化在影响物种形成过程中发挥了重要作用。洪堡属包括分布在巴西东部的48种。以前的细胞学信息包括很少的物种，仅染色体数，缺乏有关基因组大小的信息和更准确的核形态学研究。在这里，我们比较了12 Hohenbergia spp的细胞分子特征和基因组大小。此外，据报道有32种物种的基因组大小的新测量。所有研究的物种呈现2 n = 50，在凤梨科中很普遍。基因组大小（2C）从0.74到1.52 pg不等。尽管染色体数目和基因组大小具有明显的同质性。Hohenbergia，观察到明显的多态性，在中期染色体中的CMA ⁺ / DAPI ⁰带的分布以及35S和5S rDNA的位点。12个被分析物种中有7个呈现出关于35S rDNA和/或5S rDNA的异质对。因此，尽管染色体数目保守，但霍恩伯格氏菌仍显示出核型多样性。